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#1 Posted : Saturday, February 8, 2014 3:24:11 PM(UTC)
So a buddy of mine that I've been helping out recommended that I put this up, so here it is. Before I start with this guide, I would like to remind everyone that though this is a guide meant for beginners, all can benefit from it as I will cover techniques for setting up a car. This can obviously help someone new to tuning, as well as someone looking for a new way to approach a current problem. For a quick background on me, I grew watching NASCAR since I was little and currently attend NASCAR Technical Institute so that I could better understand the sport I grew up enjoying. Therefor a lot of the information in this guide comes from classroom material from the only institution officially backed by NASCAR themselves.

Now before you go off and think to yourself "Oh great, an oval idiot who thinks he can go fast just because he likes endless circles", let me remind you that you should either stop being intolerant or just stop reading this any further. There is no mechanical difference between a stock car, a prototype, or even your '94 Civic hatch. Sure, the engines are different, and so are the suspensions and bodies but once you quit being intolerant, you'll see that they all adjust in the same way. Springs are still springs, adjustable wings are still adjustable wings, and all cars still have caster, camber, and toe. Also, before you start thinking "This guy is an oval idiot, what does he know about setting up a car to go left and right", let me point out what I just said. Left or right, or even straight, these adjustments do the same thing.

Also, before I begin, let me say this. This guide isn't a magical number guide. You won't find in here what tire pressure your Mclaren P1 should be set at for Circuit de la Sarthe, or what your rear wing adjustment in your S2000 should be for your B class build at Bathurst. This guide is only meant to tell what each adjustment is, what they do, and some differences in game from real world application. The most important note to remember however, is that tuning a car won't make you any faster than you already are. In order to make a tune to get the car faster, you must have control of the car. If you want that E21 to fly at Yas Marina, you must first be able to control and post steady times with the E21 at any track. This is also why you don't see me at the top of the leader boards. I don't tune for leader boards, I don't follow the typical leader board lines, and I will admit straight up that I'm not the best driver. I prefer to race, not hot lap, and so my personal tunes fit my personal style. Hopefully this guide will allow you to tune for your personal style, whatever it may be.

Now that I have my little piece out, there are several parts to a car. There are several ways to build one. There are several ways to set them up. The possibilities of a tune are quite mind boggling because there are so many different ways and the combinations are pretty much infinite. There's trailing arm eccentrics, wheel spacers, caliper offsets, Ackerman angles, so many things. Luckily, we don't have to worry about physically building cars in this game, and we really only have to worry about 25 to 32 of them. Yay! 25 to 32 out of hundreds, but that's still... Well... 32 at most things we have to worry about right? I mean there's gear ratios, spring rates, tire pressures, caster... So much for the yay, right? Tuning a car can be a fun process for many, boring for others, but tedious for all. It's really hard to tune the car if you don't know what does what. Those 32 options? Well they really only come out to be 16, and these 16 are the ones that you need to know. Fret not, these are only what they do, and I will cover how to use them later on when I talk about how to tune the car.

Tire Pressure: Just as it states, this is the pressure the tire while it's cold. As the car runs, pressure will build up in the tire due to heat, and luckily we can see that, via telemetry. How pressure affects the car though is how the pressure inflates the tire. Even though the tire is one piece of compounded rubber that has been formulated (and built, meaning it's really not just one piece) to withstand high temperatures, it still flexes with movement. The smaller the pressure is in the tire, the more it'll flex as it sits. The higher the pressure, it'll flex more as it moves. With a lower pressure, the tire has the opportunity to grip more as there is more surface area against the track. With a higher pressure, there's less surface area for the tire to grip, so while it's moving it'll flex more to provide different areas of grip which can allow for more speed, depending on the amount of pressure.

Gearing: This is simple gear ratio, and this is how it goes down. A gear ratio is a simple formula of two different gears. You have the gear that's being driven and the gear that's driving. To find the ratio, it's driven over drive. So if you have a driven gear that consists of 100 teeth, and a driving gear of 10 teeth, it's a ratio of 10:1. This means that it takes 10 revolutions of the driving gear to turn the driven gear 1 time. This creates a mechanical advantage to get the wheels to move without destroying the driveling. And each gear can be adjusted so that each one provides a different range of mechanical advantage. Now let's say a theoretical engine in a rear wheel drive vehicle can rotate up to 10,000 times a minute. If you're in 4th gear with a ratio of 1.00, that means the transmission is rotating the drive shaft 10,000 times a minute, and the drive shaft is what goes to the rear tires. So what prevents the rear axles from rotating 10,000 times a minute and not blow up? The final drive is what you change. When you change the final drive, you're changing the gear ratio of how fast the output shaft in the transmission can can turn the axles. A higher ratio can give you more acceleration, while a smaller ratio can give you more speed. However, this isn't always the case, as I'll explain later on.

Camber: Camber is the angle at which the tire sits in relation to the car. When you look at a stock car for instance, you'll see two things common with the front tires. The one on the left side seems to be angled away from the engine, while the right side seems angled towards the engine. Well you're not imagining things, that's actually how it is. As the stock car goes through it's forces, it will want to slide up the track with high banking. The camber acts as a wedge against the banking so that as the car attempts to go up the track, the tire will get a full contact patch on the track, providing the best grip it can. But in FM5, we don't have to worry about high banking very often, nor splitting the camber angles from left to right, but camber still acts the same when you're putting a car through a corner. It's going to want to naturally slide, and camber will act as a wedge to the track surface. Positive camber is measured at the angle away from the engine. The more positive the number, the further the angle is away from the engine. A negative number is measured at the angle to the engine. More negative camber, the more the tire is angled to the engine.

Toe: Well we've got the tire angled to or from the engine, and now we have what keeps the tire straight. Toe measures how far the tire is pointed from it's center line. "Toe-in" is positive toe. "Toe-out" is negative toe. Positive toe is when the tire points to the inside of the car, and negative is the opposite. So how does that work then? Toe-in can help the car going straight down the track by keeping stable, allowing for more speed. While going through the corner, since the tires are already angled in, the car could turn better in the corner. Toe-out can cause instability down the straight, allowing for the loss of speed, but the car could turn better, since the tires will be better since it's angled to the corner already. Confusing? Yes, though it's better explained while setting up a car.

Caster: This can be a difficult adjustment to grasp, but the idea is simple. You'll hear some people use a shopping cart wheel as an example, but I personally believe that's horrible comparison, and it hardly explains what caster actually is. Now think of a bicycle. With a typical BMX bike, the handle bars are directly on top of the tire, and the tubes that steer the bike are vertical. With a typical mountain bike, the handle bars are behind the tire, and the tubes are angled back towards you. This is caster. The wheel of the tire connects to the chassis via the spindle, which is attached to the upper and lower A-arms (a typical racing chassis setup by the way) by two ball joints which are the rotational pivot points. The angle of these two ball joints lined up is caster. A positive caster is when the angle is pointed towards you, the driver while in the car. A negative caster is when the angle is pointed away from you. The mountain bike? Positive caster.

So that's what it is, now what does it do? Well think of the bikes again. Which one is easier to steer? Well most people that never rode a BMX bike would say the mountain bike because it seems the BMX only seems like it would wreck when you turned it. Well as much as that is true, it's just as false. Both bikes have the same ability to turn, but that ability differs at speed. A BMX is a trick bike. That absence of caster works because BMX bikes aren't meant to go fast, and because of the slower speeds, the bike could pretty much turn on a dime. At higher speeds though, the bike runs the risk of losing control. The mountain bike with it's positive camber becomes easier to turn, and allowing for more speed as it turns, and potentially better control. But if the caster becomes too positive, then the amount of control can go away and the car becomes harder to steer and will give you even less control of the car if you need to react quickly.

Anti-roll Bars: Better known as sway bars, they kinda sum up their purpose in their name. They're meant to help control the roll, which is actually the sway of the car. There are obviously the front and rear, and that's what they correspond to, the sway of each end. What exactly is sway when we're talking about racing though? Sway is just a simple word to use instead of speed of weight transfer. There's several other ways to adjust the sway of the car, and the game only works with a couple, but these two are simple ways to do it. For those who don't work on cars, the sway bar works the same way in a race car that it does in your personal car. It's a piece of metal that's specially fabricated so that it can twist. Because of this, it's actually a torsion bar, but because there's many different types of torsion bars in a vehicle, "sway bar" is an easy way to determine which torsion bar it is.

Now how it works is simple. Depending on the size of the bar, the car will naturally sway the amount the bar allows. Think of it this way. Say you have a piece of cardboard tube, like the tube you have when you finish up the roll of paper towels in the kitchen. If you try and flatten it between your hands, it's tough to crush. But if you grip it and twist, it flattens much easier. Torsion bars act the same way. The harder you grip and twist, the more it's going to compact. Now imagine that cardboard tube was like a slinky. You've got it crushed up and it's destroyed. But this is a slinky cardboard tube, so it unwinds and comes back to it's original shape. A thicker bar is going to take more force to twist, so when the bar is done twisting, it doesn't snap right back so easily. If a bar is too thin, it'll twist more easily and could then snap back pretty quick.

Springs: Ah, the springs, a fun and often misconstrued part of the car. For common people that don't know much about cars, the spring is often viewed as what holds the car up and allows it to move up and down. But that isn't the case. So what does the spring do then? Well, in a really odd concept, pretty much nothing but just keep the car from slamming down to the ground. However, because of the fact that majority of race cars use a coil spring (which from what I can tell, FM5 uses a variable rate coil spring for their data), they're very important. As the spring coil compresses, it exerts force on the tire. The number you see is the spring rate. Which means it takes that many pounds of force to compress the coil 1 inch. So a higher number means a stiffer spring, which in turn puts more force on the tire, where a smaller number is a softer spring, which doesn't put as much force on the tire.

Ride Height: Somewhat self explanatory, this is the height of the car. What's not self explanatory is where this measurement is taken. Ride height is typically measured at the bottom of the frame rails in both front and rear. The distance from that spot and the ground is the height, which means that just because the ride height means is as close to the ground as you can get it, doesn't mean the rest of the car is at the same height. Typically a car that is low to the ground is a fast car, however that isn't always the case in some applications.

Rebound: This is part of the shock. Well, not really part of, more like an action of the shock. Shocks are a device on the car meant to handle how a car moves weight around while moving. Rebound is the decompression of the shock. Think of it this way. As the car goes into the corner and you apply the brakes, all that weight is going to go forward, which is just simple physics. It's Newton's first law, the Law of Inertia. As the front end shifts forward and the rear end lifts up, there has to be something to ease the sudden weight transfer, and it's not the springs (which I just explained). The rear shock will decompress, allowing the weight to be applied to the front of the suspension. Rebound is just an easier way of saying decompression rate. A smaller value means the shock will decompress faster, and a larger value will decompress slower.

Bump: Part two of the shock. If weight going up decompresses the shock, then the shock has to compress so that it can be ready for the next weight transfer, and this is what bump is. It works the same way as rebound, but just in the way of compression. As you go forward into the corner, the weight will transfer forward, and the shock will compress. Once again, smaller is a faster compression rate, more is a slower compression rate.

Down force: The opposite of lift. And I'm not even trying to be sarcastic here. This adjustment isn't something on a real car that can just be measured easily. The front splitter and rear wing are typically adjusted by measurements of height and angle. Down force isn't figured out until the team combines wind tunnel data with track testing data. Luckily, FM5 cuts out that entire process. So that leaves it to what down force actually does to a car. This adjustment is simple in that you only choose how much down force you want on that end.

Braking Balance: All this does is transfer the amount of pressure between the front and rear brakes. Really a simple concept. When you push down on the brake pedal, pressure goes to both sets of front and rear disc brakes. With more pressure to the front, the front brakes will start to apply before the rear brakes allowing for more weight to be transferred to the front of the car.

Braking Pressure: Again, a simple concept. When you push down on the pedal, and the braking balance gets distributed, this is how much pressure is going to be applied to the brakes.

Differential Acceleration: You'll hear some say this is the most important adjustment ever made, while some say that it is what it is. It's rare I see any actual description of what it does though. The funny thing is, this really isn't something that's a race only option. It's just simple part choice of what you run in any car. When you accelerate, the tires are going to rotate at the same speed. Which is fine for going straight, but not in a corner. When you attempt to accelerate through a corner, the tires have to be able to rotate at different speeds so that the car can properly turn. All this does is allow you to change the difference in rotational speeds under acceleration.

Differential Deceleration: The same as what I just said above, except for deceleration.

Differential Balance: You'll only find this in AWD vehicles, and here's why. All it does is proportion how much torque is going to which end of the car.

Okay, so now we know what each adjustment is, and what it's supposed to do on paper and in theory. Now we have to apply the theories of what they're supposed to do so that you can get a car to do what you want it to do. Remember back when I said that this isn't some magical number guide? Well here's the full statement. There's plenty of places to get setups for each track you're looking for. There's the forums here provided by Turn 10, and then there's the huge contraption of every single thing ever conceived as an idea known as the internet and it's infinite amount of web forums. Now while for some people, tunes found that way may work for them, and make others wonder how the hell the car can even go forward. Then there's those that don't have the time to make their
own, so they find a tune they can work with and go with that. Now there's nothing wrong with using something that someone else made, in fact, it's actually not a bad idea to try. But there's always two problems when doing this. For one, it's the internet, and unlike what our favorite blonde in advertising believes, everything on the internet isn't always true. So just cause the person says "I can do xx.xx and hit xxx MPH" doesn't mean you're going to do the same because that tune was either made to make you intentionally slower (watch out for Admiral Ackbar, just sayin). And secondly, and 99/100 times the case, the tune was tailored to them, which means if you're going to be faster with it, you're going to have to change it (if you can change it of course). Now let's get to changing it.

If you're doing what I just stated and are changing a tune, just stick with me as I'm starting from the ground up for those who want to attempt their very own tun. But this can also help adjust different areas you're wanting to look at. Also, this is the way I like to make my setups, and is also a common way I've found out, and is also a good stepping stone for developing your own way of tuning the car. The most effective way of making a tune is to have base process to create the tune.

Edited by user Tuesday, February 11, 2014 2:20:00 PM(UTC)  | Reason: Not specified

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#2 Posted : Saturday, February 8, 2014 3:24:46 PM(UTC)
So each car after you have it outfitted with whichever adjustable parts will have a default setting. This is what we'll refer to as a baseline tune. Each car has their own baseline tune and it's rare that one will match another. Since there's nothing to change in the first place, this is where we begin to tune: Hitting the track. After you've ran the track and gotten a feel for what the baseline tune can or will do, you're obviously going to have a few thoughts. More than likely it's going to be "I need more speed" but could also be "I've got too much over steer through the corners" or "This car has way too much over steer". Well speed is going to come from the corner. The faster the car can get through the corner, the faster you're going to move around the track. In order to go through the corner fairly quickly, you have to put the correct amount of input into the car for it to corner smoothly. That brings us to our first adjustment, caster.

Caster is an adjustment that will not only help your ability to turn, but will also help you find your straight line speed. Positive caster will allow for more speed as I told you. Great for the straight, but now you have to get the car to turn. You've got physics to overcome. So how should you set the caster? By feel, comfort and speed. You'll to experiment with different angles to try and find what angle best suits the way you enter the corner. Here's what you have to keep in mind though. Just how I explained earlier, the lower the angle means the more difficulty you'll have trying to turn the car while not having enough straight speed. And too high of angle will not only sacrifice speed, but give you difficulty trying to control the car while turning.

So now the car feels better to control. And hey, you may have shaved 0.1, maybe even 0.2 seconds off your fastest or average time! Or you've probably lost some time and are starting to wonder "This guy seemed smart, but he must be stupid or something..." Well in order to make a car fast, you have to keep control of the car, and since you should hopefully have a better feel with the car, now we can start looking at getting more speed out of it. Tires. Tires are going to be a very important tool in the entire tuning process. Controlling a car through the corner is one part of making the car fast. However, just because you don't exactly feel it, the car is going to naturally have over and under steer. If you have too much over steer, it's because the rear end of the car doesn't have enough grip for the speed you're trying to enter the corner with. Under steer is when the front end doesn't have enough grip to turn the car. Now we need to see it. The best way to see it is by tire temperature, and this can be very tricky to do. In the game, we have telemetry. And for us to properly use the telemetry, we have to watch to watch it, which means we have to be on the track and driving. If you can pay attention to those while driving, well then that's great. If you can't, then don't worry. Just run some laps with the telemetry screen up, and review it later. While we can't exactly see telemetry data in replay mode now, we can still use the recording tools on the Xbox One to analyze it. Is it quick and easy? No, it's actually quite a pain. But until you can learn how to drive while reading the telemetry, then it's what you'll have to do.

So what does tire heat tell us? The amount of work load those tires are under. Generally speaking, if the rear tires are getting hotter before the front, the car has more over steer. If the front is getting hotter before the rear, well then it's got more under steer. Well instead of avoiding the topic, let's give it some speed. Tire pressure. Remember, tire pressure equates to the size of the contact patch and how it flexes. When you increase tire pressure, the rotational circumference of the tire changes as well. With a lower pressure, there's more of a flat spot on the track. But when the tires are cold, you'll always have that flat spot. As you run them, the tires will build pressure, and increase rotational circumference. So where's rotational circumference come into play with speed? Less resistance against the tire! But before we get that going, we have to make sure the tires are going to withstand it. After the caster, we got the car turning the corner better, but the car was still had too much over or under steer. Well to bring it back to comfortable, we're going to change the corresponding tire pressure. If it feels like it has over steer, take air out of the rear, giving it some grip, and same with the front. "But the telemetry shows that the rear tires are heating up faster than the front, now what?" Excellent point. I said feels like it has overseer. The lower the cold pressure in the tire, the more it will heat up (fewer air particles allowing for more movement, creating heat. Physics people, physics). If you lower the rear tires to give it more grip and the car no longer feels like it has too much over steer, you now have to correct both sets of tires. So if lower pressures cause more heat, raising them will decrease the heat. This is where we start to gain speed. Higher cold pressures allow for more speed off the bat, and since they don't wear as fast, can keep the speed longer. But there does become a point in which tires start to lose speed if the cold pressures are too high due to rotational circumference being to large, so keep that in mind. Just remember that what you're looking for in tire pressures is the combination of speed and grip, not just one or the other.

Once you get the pressures there, now you can adjust the camber of the tires. Camber is going to help you get better grip of the tires and will result in more speed. Again, you still have to be able to view or review your telemetry (or the new indicators we have for FM5), but this time even more closely. The tires will be shown in three sections, the inner, center, and outer sections of the tire. The goal of camber is to allow the tires to heat and wear evenly while getting the most grip from the tires. So here's the tricky part. Turn 10 has yet to allow for split measurements. Now you may have noticed this already. So when you look at camber angles with either the telemetry or indicators, remember you have to make your adjustment based on both sides equally, not individually. So here's the process for taking left turns. On the right sides, if the inside of the tire is heating up faster than the outside, you have too much camber. If the outside of the tire is heating up faster, you have too little. On the left sides, the reverse is true, so if the inside is heating up faster, you have too little camber. And for taking right turns, that entire process is true, just in reverse. Just keep in mind that once the tires begin to heat evenly, you may begin to lose some speed, but it's okay, you'll get that back.

So now that we've gotten the caster, pressures, and camber of the tires, there's only thing left to do on the tires, and while it's something that doesn't exactly have to be done now, it's something we may as well do now since we're just about done with the tires. Toe. Remember what I said about it, and that's really all that needs to be said. So let me go ahead and unconfundle what I had said. More toe-in can help the car turn into the corner because the tires are already angled in. Exactly the case, for the front tires. So how does toe-out also help the car corner? The rear tires since the rear of the car is physically being forced to swing the opposite direction in which you're turning. Just remember that too much an angle will not only begin to degrade your cornering ability, but will kill your speed. Don't worry, you'll notice the loss of speed before the loss of handling in most cases.

Okay, so we've just gotten the tires out of the way. Done with those right? Well not exactly. Tires are always something to come back to from time to time. You may want to check them after a ride height adjustment, or a spring adjustment, maybe even a brake balance adjustment. How often you check them is entirely up to you, but just keep in mind that tires are not a one touch adjustment. Tire temperatures are going to change as you make other adjustments, and are always something to look at if some changes aren't doing what you think they should be doing. It may just be a pressure change on one end of the car needed, it could be a camber change in one end, or it could be that both pressures and cambers need to be changed, in both ends of the car at that. The main thing is, don't forget that tires are the most important thing on the car. You can have all the power you want, but if the tires aren't there, then the car isn't worth a damn.

If the tires are the most important part of the car, then the suspension is the second most important. Some of you have probably gained a 0.5 or even a good 0.6 of a second from where you've started and some of you have only gained about 0.1 - 0.3 of a second. But you're still wondering what needs to be done because you're still close to a second behind the lead cars, and yes, that just simply won't do. I can almost promise you that you'll gain that second plus some as we start to adjust the suspension. Now I say almost, because a lot of this also depends on you. I've told you that you need to practice your lines, get your marks, find what entry works for you, learn when you can get on the throttle in the corner, which all equates to the fact that you have to learn to control the car to begin with. Now this is where you're going to be thrown around, lose control, run off the track or hit the wall, lose patience, and get so damn confused to the point you want to tear your hair out of your skull. You're going to have to change your line, some a little, some a lot, you're going to have to change you braking and throttle points, and you're going to have to pay attention to all of your adjustments and the telemetry. And if you haven't been taking notes on which adjustments work for you, then you better start taking them now.

First up on the suspension chopping block are the springs. Springs are something that a new team can spend seasons on trying to figure out a package on. Springs will give you grip, control, and speed just as fast as they can take those 3 things away from you. Now before I go into the game, let's look at a real car first. Springs come in many different rates. The lower the rating, the softer the spring, and the higher the rating, the stiffer they are. And some of these springs will come with variable rates. A stiffer spring will exert more force on the tire it's over, causing more grip and a softer spring will take some force off of it, allowing more travel for the tire. The rating of the spring will also change the height and weight of a car in that corner as well. A spring that's rated at 1500 lbs/in means that for every 1500 pounds of force that is exerted on it, the spring will compress 1 inch. So a spring that's rated at 500 lbs/in will compress and extra 2" if 1500 pounds of force is applied to it. So let's get a theoretical car that weighs 3000 pounds, and has a weight distribution of 52%. This means that the front end of the car is going to weigh 1560 pounds in the front and 1440 in the back. So let's compress our springs 2". In order to do that, we'd have to change the rates to 780 lbs/in in the front, and 720 lbs/in in the rear. Well looking at the overall shape of the car, the rear end still looks higher than the front. Now earlier I said that a car that is lower to the ground is faster in most cases. Okay, well simple. Let's compress the rear springs and extra inch and everything will be fine. Wrong. The weight of the front end would change drastically because the physical ride height wasn't changed to keep the proportional weight. Because the spring is softer, that end would compress more towards an inch yes, but because the ride height wasn't changed to counteract that, the weight would also drop in that end, raise in the front. So your new spring rates mean nothing.

Now here's the saving grace we get in this game. Ride height is adjusted by a multitude of devices attached to the frame that helps hold the spring in place. When you adjust this device, you change both ride height and pre load of the spring. When the spring goes to a softer rate, the corner drops to rest on the spring, and ride height lowers. So for actual effect, the ride height has to come back up, and then the spring will compress that one inch. The game automatically does this for you. So while the original wrong answer still holds true, the game helps you so that you can say yes, the springs has now compressed and inch. Now let's make that spring compress another inch, so the rear springs at 360 allow that right? Well with the game's help, yes it does.

So what the hell does that all mean anyways? This goes to show you spring rates and what they do. If the rate of the spring goes below the weight of that end of the car, the weight itself will lower, and affect the other end. Now hopefully you have a much better concept of springs than you did before, and now you can learn how to adjust them. If you truly want to make sure that you get the most out of your springs, you're going to to have the time and patience to do so. A point to start with this is to do what I just talked about. Match your spring rates to your end weights, and only compress them those 2". This will allow you to have a balanced car that should still have close to your original handling. Now should is the key word, which means it's going to be different. How much it varies will depend on the track, the car, and your current line. This is where the telemetry screen comes into play. On the screen that shows your lateral and longitudinal forces, labeled in G's. A G for those who don't know isn't a "gangsta", but a gravitational force. 1 G is the equivalent to the gravitational force applied by Earth's gravity. Lateral for those who didn't pay attention in science (or geography for that matter) is sideways, longitudinal is front to back.

So how do gravitational forces work with adjusting springs? Simple. Standing still, the car weighs only so much. Going 180 MPH in a straight line, the force against the air, also known as down force, is going to add weight to the car. Going 180 MPH into a corner going to shift that weight to that end. Springs could possibly tuned much easier now that we could see the directional forces, but once again Turn 10 doesn't allow for the splits. If you couldn't figure out why, hopefully now you know, since for the amount of cars in the game, they would have to get corner weights and apply much more physics data to work for different sets of cars. Now we don't know what the car weighs with the down force at speed is, simply because we don't have access to that data, and even very few teams can even come close to that data on the track. So that hurts us in trying to figure out what our springs really should be, but hey, that's what makes setting up a car so "fun". We can however figure out how the weight is shifting in the turn and the straights, and that's by gravitational forces. Let's go back to our current example numbers right now. 1560FW/780FS and 1440RW/720RS. If we take a turn and we experience 1 G, then nothing's changed. If we experience 1.25 G's to the rear, then the weight has shifted to the rear 1 1/4 times, meaning that our weights in the turn will be 1170FW/1800RW. Well now we can see that the front springs aren't compressing a full 2" and the rear are compressing even more.

So I just mentioned that we can't see down force, right? Well here's things can be helped in the down force department. The down force adjustment. Now I'm going to give out some theoretical numbers because I don't have an engineering degree, so don't please don't quote me on exact numbers. So we figure that going down the straights, this car's acceleration puts about 1.05 G's to the rear end. So it's at 1482FW/1512RW and with the springs at 780FS/720RS, the front end compresses down 1.9" and the rear 2.1". Let's throw in the down force generated by moving at a single point in time. As you go faster, down force increases (this is why I don't have actual numbers because I don't know the equations for mass, velocity, and negative lift). Let's say you're 160 MPH in this car, and you've got 1000 pounds of down force on your car. This car now has an extra 1000 pounds of weight to it. It's no longer a 3000 pound car, it's 4000. So the car's moving weight is now 1900FW/2100RW, compressing your springs 2.4"/2.9". There's nothing you can do about that extra 1000 pounds. However, you can add to it. If your down force settings are at 75lbs/135lbs, you're adding 75 pounds to the front and 135 pounds to the rear. So while going down the straight, extra weight would slow the car down, that extra weight will help it turn.

Okay, so I've avoided saying how to adjust springs it seems, and throwing down force in there doesn't seem to help. But when you look at it, I've explained both of these adjustments exactly for what you need to adjust. What you need to look at now is handling, speed, and tire wear. Softer springs generally run faster, as they are able to compress more and lower the car. A car lower to the ground will go faster since there isn't as much turbulent air underneath, and tends to handle better as down force is able to help keep the car pinned to the ground. At the same time, stiffer springs allow for more force on a tire. And the whole while, you have to pay attention to tire wear. If the tires are wearing out faster than your previous runs, then look at your notes and notice where wear rates were at with lower wear. If you don't want to directly change the springs, then modify how much down force you're applying to each end. That way you can keep those same handling characteristics in the corners, but you don't have to worry about your corning ability directly related to the springs. Add or remove some down force to make those springs more effective. If the speed wasn't there, then consider your line. Maybe change your braking point so you're not as hard on them, or maybe change your line in the corner. Instead of trying to hold the inside line consistently, try running a little wider. If a track can hold cars 4 side to side in the turn, then you've got 4 different lines with many different braking and throttle points. If you think that you may need change your line up a little, go right ahead, there's plenty of track to do so. So what? Just because I'm an oval guy means I don't know what the term apex means? If that were always the case, then why aren't oval racers always fighting for the direct apex? It's difficult to change lines in a corner that has no banking, but if you have banking, then use it. After you figure out your springs, look back at your tire temps and make changes to pressures and camber, as now is a good time to do so.

So now we've got the springs set after quite some time (or to the point where you needed something else before you started seeing springs in your dreams), let's move to ride height. Now as I just covered in the springs, changing ride height is going to change the weights of your ends. However, this change is going to more dramatic in weight than what the springs did (thanks to how the automatically adjusts those attachment devices), so beware when you make changes in ride height. A simple change of 0.2" could easily be more speed or your car off the track. Again, the lower the car, the faster it can go. Now, I've been saying this quite a few times, so let me use this as the point to further explain how this isn't a magic number guide. A big factor of ride height isn't just the front end, but more the rear end. And the reason the rear end is a bigger factor than the front is because of the spoiler. That wing is a major component of drag and loss of speed, but one of the biggest things to help you turn. Also throw in that some vehicles are built that the rear end of car is higher. So with that in mind, if you're on a track that's got some major elevation changes, the front end may have to raise a little so that you don't dig the front end of the car into the track. So while having that front end a little higher could end up hurting you in speed, it may actually help you out overall. Each car will apply this differently to different tracks, so don't always stay in the mindset of always low. So here's some advice on adjusting the ride height.

As the car goes forward, it's got to push through the air, obviously. Well the air is respectively going to go where it's easiest to go. Through the grill is the first main spot, then over the hood, flowing over the car, then the sides, and finally under the car. Well since the under the car is such a small space, the air become extremely turbulent. And turbulent air is going to make the car very upset. Now most cars are built so that air can escape from underneath and create stability, but the less air under there allows for a more stable car. A car with a lower center of gravity is a car that will grip the track more efficiently, and in turn, will result in a faster car that will do what you want it to do. So here's the point to adjusting ride height. Get it as low as you can while avoiding the bottoming out of the car (where it scrapes the track and sends sparks everywhere) on a consistent basis, and so that you can still turn the car without it having too much under steer. The lower that wing goes without down force will give you more speed, but more speed also means an earlier braking point. So if you get it so low that you have to let off the throttle or brake much earlier than everyone else, then the rear end is too low. Remember, you have three other ways to lower the car, tire pressures spring rates, and down force if you feel the need to. After you adjust the ride heights, look at the tire temps and adjust accordingly, and if feel the need to as well, make a few changes to the springs as changing your ride heights will affect end weights.

We're just over half through this and we've got a majority of the hard stuff out of the way. Most of the rest are simpler to adjust and don't take but a few runs to figure out. Now that we've got the car handling like we want, and hopefully a lot more speed out of it in the process, now we need to fine tune a little more speed out of it. First up, let's work the gearing. Each car has it's own power range, and set of gears. Most adjustable gear sets typically adjust 6 gears, plus the final drive, though it's possible can only adjust the final drive if that's the kind of car build you're forced to run. In either case, with the car and track you've chosen, keep an eye on your shifting habits and what gears you use. Just because you have 6 gears available, doesn't mean you have to use all 6. Focus your ratios so that you're getting the most speed you can out of the gears you use more often while still being able to get out of the corners. This is where the differential plays in as well. Depending on your drive wheels, differentials will vary for front and rear, but that's what they change. If you have a FWD, you'll change the front. RWD, the rear, and both if you have a AWD. A lower percentage means the tires won't rotate a much different speed, a higher percentage means they will rotate a much different speeds. Either way, that's an adjustment you'll have to make when working with your lower gears so that you can exit the corner more efficiently while still feeling comfortable with the most exit speed you can get. A lot of people will tell you different percentage numbers, but in reality, it all comes down to how you exit the corner.

Next, let us play with the anti-roll bars. Now the sway bars can leave some interesting effect. The kind of car you drive will more than likely dictate which end you focus on. RWD with a heavier front weight will focus mostly on the front bar, and sometimes the rear bar won't even be needed. FWD will put more focus in the rear since there's no power back there, so the rear end could just possibly swing out. Of course it still depends on how you attack the turns. Simply put, the thinner the number (I like to view the numbers as bar thickness in mm as you typically deal with these in thickness measurements), the less over steer in the front on corner exit. To thin and you risk too much over steer in the rear on corner entry. For the most part they'll tend to be proportional to the spring rates. A typical method would be the lower the spring rate, the bigger the bar, but just keep in mind a spring rate that's minimal doesn't justify a maxed out sway bar.That leaves us with two adjustments left, the brakes and shocks. Brake balance is simple, more pressure to the front will increase over steer, where more to the rear will increase under steer. If you like the stopping power but don't like the corner entry result, go back to your sway bars and thicken or loosen the rear one, according to the condition you're fighting. And brake pressure is a matter of how hard you have to apply the brakes. Higher pressures allow for a faster stopping distance with less effort, but too high could lock the wheels too easily and cause over or under steer depending on balance. Lower pressures mean longer distances with more effort while lowering the risk of locking the wheels up, but too low risks not being able to stop in time. Now before we move to the shocks, make sure you have your springs where you want them, because the shocks are going to make you second guess them.

Let me take a moment here and let your brain rest for a second. I've just dumped a lot of information, and sometimes it can be overwhelming in one shot. So a while back ago, I signed up for an online racing service (won't name drop, but not hard to figure out) and started racing late models in an open setup racing series. The first track I went to was a little oval formally known as USA International (the track in life has been demolished). Well as fun as this track was, I had absolute hell coming out of the corners. The track was barely half a mile in length, and the corners were extremely tight. You couldn't even fit 3 cars in the corner without wrecking half the time if you were trying to be competitive. I found it fun. Anyways, was mad this track a nightmare for me was corner exit. I could fly into the corner no problem, but where I'd lose race pace was coming out of the corners. I had busted my tail on the setup, tried different lines, and put the car in to the wall so many times, but I just could not figure out how to get back on the throttle with out the rear end swinging like a baseball bat and still hold pace down the straight. I made friends with a guy who knew how to set the late models up and he even tried helping me with what was wrong. "Track-bar good?" "Yep, rotates beautifully." "Springs okay?" "Not too tight or loose in the corner, wear and temps are okay." "Weight balance is fine?" "Nothing out of whack, I just can't get off the corner for some reason on the throttle and I'm loosing my mind trying to find the reason!" "What about your rear shocks?" "My what?"

Shocks, like stated earlier, are a weight control device. Now I explained how they work. But the question here is how do you adjust them. Here's a good tip to remember as you adjust these. Bump is for driver comfort, rebound is for weight control. Let's break this down to understand it better. As you go down the straight and approach the corner, the shocks are virtually static. They're not really changing drastically, only changing with the surface of the track. An older track will have more bumps, while a repaved track is going to be pretty smooth. Either-way, if your shocks are tuned right, you're not going to feel a lot of them unless it's a major feature. But as you get to the corner, when you let off the throttle, the sudden stop in acceleration is going to cause the car to shift forward. Once you start to apply the brake, no matter what the bias is, the car will shift even more weight to the front. That's when the front shocks will compress. If the front shocks are too soft, they won't be able to support the weight transfer and you'll feel like the car is going to turn sideways and flip over. If they're too stiff, it'll feel like the car didn't even stop moving and you'll find yourself with too much under steer. So once you figure out your front compression rate, you can have a smooth entrance. Now you have to get off the corner with throttle. Since you're already off the brake, you won't have much weight transfer forward if any at all. But once you get on the throttle for exit, the car is gonna shift it's weight backwards. If the rear shocks are too soft, it'll feel like the car is being slammed back and it'll generate a lot of over steer (which is the problem I was having in the story I said earlier) since the rear tires were still trying to turn. If they're too stiff, then it'll feel like you have no power at all, and make it seem like you can't get speed off the corner. So bump is for driver comfort.

Rebound is for weight control. Well when you go into the corner, the rear end of the car comes up due to the sudden weight transfer. If the rear shocks are too soft, then the car will launch the rear upwards and you will actually have over steer and spin on entry. If they're too stiff, then they won't decompress fast enough and the rear end will start bouncing up and down, generating over steer and causing you to spin from the constant bouncing as the car tries to settle itself after entering the corner. This will be an odd spin though. As you go through the corner and the rear end starts bouncing, the compression will make you feel like there's a lot of over steer, and you'll probably try to correct yourself by turning the wheel to save yourself. Well that'll stop the over steer feeling because the car will finally stop bouncing. But if you turn the wheel too much, once those tires make contact if you're still in gear, they're gonna grip and you're going to go in the direction you're turning, sending you up off the track. Once those shocks are set, you've still got to come off the corner. Well getting on the throttle you should be set. But the front shocks still have to decompress. If they're too soft, then it'll push the front end up causing you to generate over steer off the corner or even under steer, depending on your exiting line. Over steer if you're hugging the apex through the corner, under steer if you hit the apex and move across the track. If they're too stiff, the front of the car is going to lift up with acceleration and the front end is going to bounce around generating over steer off the corner and causing you to let off the throttle to settle the car down as you slowly ease back into it.

Once you finish tuning your shocks, you're pretty much set. Just remember that throughout the entire setup, don't forget to look at your tires. If you feel that something should be changed, don't be afraid to change it. The biggest thing though about creating your own tune is that you only hold yourself back if you stay limited. Feel free to experiment with different cars and tracks. Learn what works for you and doesn't work for you. I laid down a lot of information, and for the most part, everything holds true. However, you may find yourself in a spot that my guide doesn't quite help you or give you the answer you want. The more research you do, the better you can become at creating your own tune because you'll actually be developing your own process of creating a tune. A driver that can drive pretty well without a tune can be a weapon. That driver who knows what a tune allows for can be hard to beat. But if that driver knows how to make a tune effectively for them, well I'll just look for your name at the top of the leader boards then.
Rank: On the Podium
#3 Posted : Saturday, February 8, 2014 3:50:05 PM(UTC)
Thanks K Steinwand!

This is great! I am complete beginner (first ever gaming unit=XBox One, and, first ever game=Forza 5) and it has been a challenge to learn how to properly tune. I've seen many videos, read a ton of write-ups, have downloaded many builds/tunes from others, as well as, looked at many of the open-spource tunes to continue learning. Sometimes I am not sure how much of an impact the tune has versus my abilities with the controller (though both are important!). Other times it is hard to distinguish, example: in various races (see my post on the Shelby 2013 GT500, http://forums.forzamotor...e-w-o-hitting-walls.aspx) I pretty much got the same time with 2 purchased tunes and my own.

I'll keep learning. Again, thanks!


DJ Saoco
Rank: Racing Permit
#4 Posted : Saturday, February 8, 2014 3:53:03 PM(UTC)
No problem! Thanks for the read, I know it's pretty long lol.
Rank: C-Class Racing License
#5 Posted : Saturday, February 8, 2014 4:06:26 PM(UTC)
You can type I'll give you that! Nice write up by the way, it was good to read.
Everything you said there in your 9511 words is exactly what everyone should read.
Great job - Anyone who annoys me about my tunes I'll make them read this!
RR
Rank: Driver's Permit
#6 Posted : Saturday, February 8, 2014 8:50:12 PM(UTC)
This is a great explanation of real world application of the settings. This is exactly the bit of information I've been looking around for just for an FYI in addition to the multitude of info about how these "physics" work in game... Thanks for the write up....
Quote:
To achieve anything in this game you must be prepare to dabble in the boundary of disaster. - Sterling Moss
Rank: Driver's Permit
#7 Posted : Saturday, February 8, 2014 10:18:17 PM(UTC)
thanls u tought me alot
Rank: Racing Permit
#8 Posted : Sunday, February 9, 2014 6:46:34 AM(UTC)
You're welcome guys. I will say that it's hard at some points for some of this to work the way it should in the game, but at the same time FM5 has obvious limitations for reasonable reasons. If we could split the car into 4 corners, it'd be a lot easier to work with, but like I was saying about the spring rates, Turn 10 would have to get a lot more data on some of these cars that they may not even be able to get data on in the first place. But for the most part, I'd say that FM5 is the first console game that represents actual mechanical theory much closer than others. A big thing to keep in mind is that this is still a game though, so there will be points that this guide doesn't cover well, and I won't lie about that. Hence why I said to look at other sources as well. But I'm glad to hear that this read is helping some of you understand more about the car and how to tune it. Just think, what took you 10-20 minutes to read, I spent 3 weeks in a classroom to learn most of lol.
Rank: Driver's Permit
#9 Posted : Sunday, February 9, 2014 10:09:43 AM(UTC)
THANK YOU!
Rank: D-Class Racing License
#10 Posted : Sunday, February 9, 2014 10:18:18 AM(UTC)
Thanks will probably refer back to this often
Rank: A-Class Racing License
#11 Posted : Tuesday, February 11, 2014 10:30:49 AM(UTC)
The suspension aspect is where I feel like I needed to improve in my tuning infancy.

So I have a couple of questions or observations that i could use comment on.

Springs.
This is more in line with the weight balance of the car as it applies to straight line speed/ to incorporate down force? Ex If I had a 50/50 weight distribution with no downforce added I would essentially want equal spring rates?
Under what scenario would I want to change the balance? higher or lower spring rate weighted front or back how does that affect the cars handling?

Ride height
(lower is better- got it, fairly intuitive- but I've been finding raising the front end seem to be benificial (curbs, ovals) but Im wondering if maybe I should have been changing something else (rebound/ bump) before adjusting the front ride height higher? On Indy it seems to be fairly benificial on the Zonda, and it actually showed changes in the 0-60 and 0-100 acceleration benchmarking.
Could you explain this? Is it by raising the front I essentially was making front spring stiffer making the rear end "lower", more weight to the rear which of course would help out acceleration?

Rebound/ bump.
So what I got from this is rebound is what "presses" the car into the ground (not really that is the weight on the springs), but by controlling how little it gives it allows the weight to make tire more of less engaged to track. So more on the rear (stiffer) actually effect the front end and visa versa? Or do I got that all upside down?
So said Super basic stiffer rebound in rear than front would create more oversteer in braking and more /stiffer front would cause more acceleration out of corners?
Bump is what I would change (probably keep the same ratio as rebound and go softer for lines that include curbs (bumps)? Where stiffer would benifit by keeping a more stable ride allowing the car to be set up for weight transfer quicker?

*** I could be totally wrong. I'm just trying to work through it. So I can get a base for how to change it so the planned and desired outcome are more in line. Because I basically read the description over and over and do incremental changes and 10 laps and see if it helped or not. I'd rather have some sort of understanding and make deliberate moves to go in the direction I want to go. Saving time.

Thanks for helping and I loved the analogy of castor makes total sence to me. But I was finding that closer to zero (excluding extremes) helped the zonda on turns at Indy oval. 2 was better for me than 5? Where your analogy leads me to believe that I wouldn't want to do that and I would rather a higher number. Is it because the banks help the turning so the greater turning ability is being aided by banking so it makes it better in that scenario?

Edited by user Tuesday, February 11, 2014 10:37:14 AM(UTC)  | Reason: Not specified

Rank: C-Class Racing License
#12 Posted : Tuesday, February 11, 2014 12:16:09 PM(UTC)
Questions:

Quote:
When you change the final drive, you're changing the gear ratio of how fast the output shaft in the transmission can can turn the axles. A higher ratio can give you more speed, while a smaller ratio can give you more acceleration.


Is this backwards? If the driven gear is big and the driving gear is small, you get more torsion to the driven gear = acceleration. So, a higher ratio should equal > acceleration, and in reference to the game, when you increase the Final drive, you increase the acceleration.

Quote:
While going through the corner, since the tires are already angled in, the car could turn better in the corner.

Quote:
Toe-out can cause instability down the straight, allowing for the loss of speed, but the car could turn better ...

Emphasis mine. Those two statements seem contradictory. Which one would help you turn better?

Quote:
since the tires will be better since it's angled to the corner already...

You lost me here. The tires will be better?

Quote:
Bump: Part two of the shock. If weight going up decompresses the shock, then the shock has to compress so that it can be ready for the next weight transfer, and this is what rebound is. It works the same way as bump, but just in the way of compression.

Emphasis mine. Suspected typo, you need to swap the words, "rebound" and "bump" in the two sentences in the bump explanation section.

Also in the Bump section;
Quote:
Once again, smaller is less resistance, more is higher resistance.

I think it would be easier if you did a similar explanation to what you wrote on Rebound and said that it is "compression rate" instead of "resistance" so it is easier to understand.

I'm reading during lunch, so I'll finish a bit later.


Rank: Racing Permit
 1 user liked this post.
#13 Posted : Tuesday, February 11, 2014 12:29:51 PM(UTC)
Ooh, questions, I like questions lol. Okay, so let me try my best to sort what I believe you're asking.

1) Spring adjustment depends on three things. Vehicle weight, down force, and gravitational force. Now with your example of 50/50, beginning with equal rates isn't a bad idea. It'd give you a good idea as to how the vehicle is dispersing it's weight as you run through the corners. If you're not running any adjustable down equipment, then it's fine to apply that you have no extra down force aside from what's naturally there. In that case you'd have to work off not just feel, but telemetry as well. Using the page that shows the directional forces applied to the car, you can fine tune the springs to where you feel they should be mathematically. For instance, you see an average of 1.05 G's applied to the rear, I may see that applied to the front instead, so we'd get two different numbers which is perfectly fine. How you'll fine tune them in the end is by tire temperature. If you need more over steer, you'd increase the rate in the rear, under steer you'd decrease. However that doesn't mean you'd directly adjust the rear. Maybe you'd feel it would work better by adjusting the front which is fine too. Just flip the adjustments. Does that make sense?

2) Ride height. You bring up a good point, and you're not wrong. This is something I leave out of a basic guide for the simple fact that unless you know what you're doing, raising the front higher than the rear, while it can give you more speed, can also cause instability of the car since the car isn't being tuned for that idea. If you want more information regarding that, send me a message and I'll explain further.

3) Shocks are tricky to grasp at times. They don't have any direct effect on how much traction the tires get. That's more dependent on alignment and springs. Shocks are going to have more effect on how weight transfers in the corners and under acceleration. So for instance if you had a soft compression rate in the front (low bump) and soft decompression rate in the rear (low rebound), odds are good that you'd launch the rear end of the car up in the air if you slammed the brakes at a high rate of speed. And then coming out of the corner, the car would feel unstable because until you kept a steady acceleration out of, letting off the throttle would bounce the car because of sudden weight transfers between front and rear. Unlike some adjustments, shocks don't exactly follow ratios. In fact, they don't follow any kind of ratio. Shocks are entirely dependent on how you handle corner entry and exit, which I stated that they'll make you want to rip your hair out. Don't worry, you don't have to feel bad about not understanding them. They take application time to figure out which adjustments work best for you. If you feel like you're not getting a grip on them, feel free to take a break. They're not a 5 second adjustment.

Now you brought up the Zonda and the corners on the Indianapolis oval circuit. Don't forget what I said. These theories will apply true in a lot of cases, but not every case. The Zonda isn't like a P1 or a C7 or even a S2000. Some cars are obviously built in different ways, so variables like weight and aerodynamics. Some cars will require you to do more research if you want to learn how to tune properly in the correct ways. The corners at Indianapolis are sharp left turns. Not a lot of caster is needed for them (for the simple fact we can't split the caster) so being closer to 2 degrees may work for you and the car your in.
Rank: Racing Permit
#14 Posted : Tuesday, February 11, 2014 12:58:16 PM(UTC)
Sorry, was responding to the post above and didn't see this.

Quote:
Quote:
When you change the final drive, you're changing the gear ratio of how fast the output shaft in the transmission can can turn the axles. A higher ratio can give you more speed, while a smaller ratio can give you more acceleration.


Is this backwards? If the driven gear is big and the driving gear is small, you get more torsion to the driven gear = acceleration. So, a higher ratio should equal > acceleration, and in reference to the game, when you increase the Final drive, you increase the acceleration.


No. The ratio is meant to show how many times the driving gear has to rotate to get the driven gear to rotate 1 time. Sorry if not mentioning this confused you.

Quote:
Quote:
While going through the corner, since the tires are already angled in, the car could turn better in the corner.

Quote:
Toe-out can cause instability down the straight, allowing for the loss of speed, but the car could turn better ...

Emphasis mine. Those two statements seem contradictory. Which one would help you turn better?


I mentioned that it would sound confusing and I would explain later. Please read my second post.

Quote:
Quote:
since the tires will be better since it's angled to the corner already...

You lost me here. The tires will be better?


Sorry, meant to say be more efficient. I don't always have the best word choice lol.

Quote:
Quote:
Bump: Part two of the shock. If weight going up decompresses the shock, then the shock has to compress so that it can be ready for the next weight transfer, and this is what rebound is. It works the same way as bump, but just in the way of compression.

Emphasis mine. Suspected typo, you need to swap the words, "rebound" and "bump" in the two sentences in the bump explanation section.


You caught me on being human lol. I had to convert this guide from another, which meant I had to reverse some things for "order of adjustments". For instance in the original guide, springs came before tires. Same thing here, bump came before rebound. Apparently I didn't catch that in my self editing process.

Quote:
Also in the Bump section;
Quote:
Once again, smaller is less resistance, more is higher resistance.

I think it would be easier if you did a similar explanation to what you wrote on Rebound and said that it is "compression rate" instead of "resistance" so it is easier to understand.


If this confuses people then I'll simplify it so that it's known the encounters resistance to compress or decompress.

Quote:
I'm reading during lunch, so I'll finish a bit later.


I hope that once you read the second post, it'll clear some things up for you.
Rank: C-Class Racing License
#15 Posted : Tuesday, February 11, 2014 2:07:49 PM(UTC)
The two following statements cannot both be true;
Quote:
A higher ratio can give you more speed, while a smaller ratio can give you more acceleration.

Quote:
To find the ratio, it's driven over drive. So if you have a driven gear that consists of 100 teeth, and a driving gear of 10 teeth

^-- By you definition, the ratio is 10 teeth:tooth in the driven to drive relationship (it's the same as 10 turns of the drive gear to get one turn of the driven gear, or more accurately, 1/10th turn of the driven per drive). If this is a high number, it means that there is a lot of rotational torsion (less effort to rotate the shaft) not a lot of speed (distance traveled by the car's tires per second). In order to create a lot of speed, you would need to rotate the shaft a lot of times and it would be better (easier, more efficient) to have a sub-1.0 gear ratio.

Driven / drive = 100 / 10 = 10:1 <-- this is a high ratio of driven teeth to drive teeth. This equates to high torsion (increased acceleration) because the drive gear uses less power for the exchange of more distance traveled to get a turn of the driven gear. This is the mechanical advantage, less effort to move a mass through a distance (rotating the driven gear = power).

Here, think of this;

On a ten-speed bicycle, you usually have bigger gears in front (drive gears) and smaller gears in back (driven gears). If you put the chain in the smallest front gear (40 teeth) and the largest back gear (20 teeth) the driven:drive ratio = 20:40 = 0.5. We know from 1st hand experience that this is the easiest gear to pedal, and thus we can get the greatest torque per force on the pedals, meaning we can accelerate the weight of the bike + human most easily.

Now put the chain on the biggest gear in front (52 teeth) and the smallest gear in back (15 teeth) and you get a driven:drive ratio of 15:52 = 0.2885. Which we know from 1st hand experience will produce the greatest distance traveled on the circumference of the tire per rotation of the drive gear (produces the most speed).

Try to start your bike in the smallest:biggest configuration and you will have a very difficult time starting the bike. Conversely, try to go down a steep hill in the biggest:smallest configuration and you will have your legs fall off because you haven't been keeping up with your spinning classes at the Y...not to mention you probably can't do 200+ rpms.

The higher ratio = >acceleration
The lower ratio = >speed

If I'm screwing this up, please help me understand.

I'm human too, you should read my post on OS corner entry vs. OS corner exit to see just how fallible I am, so I can completely understand. Not to mention, it is a gargantuan effort to simple write this stuff to be understandable to us laymen, so big kudos to you, and I'm enjoying the reading so far!

Edited by user Tuesday, February 11, 2014 2:09:51 PM(UTC)  | Reason: Not specified

Rank: Racing Permit
#16 Posted : Tuesday, February 11, 2014 2:14:39 PM(UTC)
I hate being dyslexic... I did read that by the way, and I got a good laugh from the pic. I've done that mistake before too, although not with the shocks lol.
Rank: C-Class Racing License
#17 Posted : Tuesday, February 11, 2014 2:19:38 PM(UTC)
More questions:
For the purposes of our tuning, do we assume that the aero downforce is a static value, or do we know that Turn10 understands that downforce and its counterpoint lift, are geometric in nature? I guess what I'm asking is, even at 10mph, there should be some resultant downforce and at 200mph the downforce is surely greater than the adjustment allows for, so what does the adjustable values that we are presented with in the game represent? Where does Turn10 get the arbitrary amount of 137lbs for the Forza rear wing? Is that at a particular speed, or is that a standards based value given based upon the angle and surface area of the wing?

Dyslexic and ADHD here...so, it's easy to hyperfocus on stuff and not see that I'm doing something backwards. I had been working on an AWD Ford GT earlier and was consistently adding more OS everywhere, so when I started working on the Vantage, I put some OS in the Springs and then I guess my brain just started lowering F and raising R dampers on autopilot...getting old stinks. I don't envy my wife once I get dementia, LOL.

Edited by user Tuesday, February 11, 2014 2:24:15 PM(UTC)  | Reason: Not specified

Rank: Racing Permit
#18 Posted : Tuesday, February 11, 2014 2:26:19 PM(UTC)
Fixed my dyslexic moments. But as much as I would love to answer that question, I have no answer. You'd have to try and get a hold of them for that answer. And in my experience, it's extremely difficult, if not impossible, to get data from developers in regards to how they code variables such as that. I tried asking a developer for another game if their code was modified for their upcoming game so that the cars didn't look like they were attempting to launch into space. He responded by asking if I meant the ride height, and I told him that a pitch rate such as that wouldn't allow for the speed it was allowing in their current game. I've yet to get a response lol.
Rank: A-Class Racing License
#19 Posted : Wednesday, February 12, 2014 4:29:53 AM(UTC)
Good read Steinwand, very educational. I´m no tuner by no means, but I now feel the urge to experiment with all the settings :)

But I have one question about brake pressure. BP is the pressure applied to the brakes in relation how much you pull the pedal/trigger right? I´ve seen many tuners use 120% and more when they tune a car, but surely the braking performance has to be the same at, or near locking threshold regardless of BP? With the same car, setup and no ABS that is. Or have I missed something?

Edited by user Wednesday, February 12, 2014 4:31:40 AM(UTC)  | Reason: Edit

Rank: Racing Permit
#20 Posted : Wednesday, February 12, 2014 8:22:53 AM(UTC)
Setting your brake pressure is mostly up to you. Overall pressure on the brakes is dependent on how you brake anyways. If you apply full pressure on the trigger with 120%, you'll apply about 60% when pulling the trigger at 50%. So in essence, it's more an adjustment to how much you feel you have to apply the brake. Does that make any sense?
Rank: C-Class Racing License
#21 Posted : Wednesday, February 12, 2014 8:25:27 AM(UTC)
Whew, got through that read, and that is a lot to absorb. Needless to say, I need to Favorite this thread some I can refer back to it. I've got so many notes on my desk right now that I am going to have to take time just to summarize the notes! LOL

Great write up K, and hats off to you for putting in the time to put this down. If it took me that long to read it, I can only imagine the hours taken to organize the structure, thoughts and layout, let alone type it.

I hate to ask, but maybe a reference guide or summary at the end?
Rank: Racing Permit
#22 Posted : Wednesday, February 12, 2014 10:28:18 AM(UTC)
Like a adjustment quick guide table? I don't do those, sorry. I dislike those because it becomes too much of a 'do exactly this' when 'this' doesn't even apply to the situation, so one can easily get confused, frustrated, and give up on the whole process.
Rank: A-Class Racing License
#23 Posted : Wednesday, February 12, 2014 10:33:52 AM(UTC)
Originally Posted by: K Steinwand Go to Quoted Post
Setting your brake pressure is mostly up to you. Overall pressure on the brakes is dependent on how you brake anyways. If you apply full pressure on the trigger with 120%, you'll apply about 60% when pulling the trigger at 50%. So in essence, it's more an adjustment to how much you feel you have to apply the brake. Does that make any sense?

Yeah, it does. Thank you :)
Rank: R-Class Racing License
#24 Posted : Friday, February 21, 2014 3:44:00 PM(UTC)
I've read approximately half of this so far but it's good to see something like this on here, I'd also like to add a few things too.

Firstly, Don't underestimate the effects simple geometry changes (Toe, Caster and Camber) can make, I've tuned some very nasty habits out of cars using only these three and the telemetry screen.

Secondly, That telemetry screen is priceless when it comes to tuning, many people would kill for such a system in real life and it's the only readout of information at your disposal so use it.

Thirdly, If you find yourself still at a loss as to what each adjustment does then simply experiment and find out, it's sometimes helpful to only purchase certain adjustable items so that you physically can't change other settings, I tend to find myself learning more when I'm restricted to only a few options rather than having an enormous selection to choose from.
Rank: Racing Permit
#25 Posted : Monday, February 24, 2014 12:43:32 PM(UTC)
Originally Posted by: GTPChristianC Go to Quoted Post
I've read approximately half of this so far but it's good to see something like this on here, I'd also like to add a few things too.

Firstly, Don't underestimate the effects simple geometry changes (Toe, Caster and Camber) can make, I've tuned some very nasty habits out of cars using only these three and the telemetry screen.

Secondly, That telemetry screen is priceless when it comes to tuning, many people would kill for such a system in real life and it's the only readout of information at your disposal so use it.

Thirdly, If you find yourself still at a loss as to what each adjustment does then simply experiment and find out, it's sometimes helpful to only purchase certain adjustable items so that you physically can't change other settings, I tend to find myself learning more when I'm restricted to only a few options rather than having an enormous selection to choose from.


Couldn't agree with you more on that. It just sucks that we can't use the telemetry during replays. Thanks for the response on this though. You seem like you already know what you're doing, but I hope that you might be able to pick something else up out of this lol.
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