Hi guys what's up? I thought I give you some insights that I learned from tuning in FM5 & 6.
I'm a long time Forza player started with Forza 1 all the way up to FM6. I used to race with other people tunes and only started in FM5 with tuning myself knowing that this would be a long and cumbersome journey :-)
I usually drive and tune only cars I would personally buy and drive and I generally don't use so-called leaderboard cars. Instead I tend to choose cars that nobody else drives and try to push them to the limit. I usually do multiplayer lobby racing so for all of my cars I'm aiming to create a general purpose build & tune that works on most of the tracks. My main class is B right now with some minor C/A/S/R racing.
Notes before reading:
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I often refer to car chassis and suspension stiffness as influencing factors for tune settings. These refer to "built-in" properties of a car that can't be changed and are part of the car model in Forza. In general older cars tend to have more flexible chassis and suspension while modern cars and especially race cars have stiffer chassis and suspension.
There are also in-between car types possible, e.g. think of a historic race car which may have a stiffer chassis than a modern production car but maybe a less stiffer suspension.
Another note:
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This guide is not intended to describe how the different tuning parts like ARBs, springs etc. affect car handling or how to dial out over- or understeer. This has been already described numerous times especially in these excellent tuning guides:
I urge everyone to read through these guides to get an understanding what the different tuning parts of a car do and how they affect car handling before continuing with this guide.
This guide focuses on HOW to setup the different tuning parts and provide suggested RANGES for tuning parameters.
TiresI have a simple rule for setting up tire pressures and have yet to find a better method:
- Stock / Street: 28
- Sport: 28.5
- Race: 29
Reasoning for different tire pressures is that besides grip tires also provide a basic level of rigidity and therefore control. Softer tire compounds like Sport or Race compound provide more grip but also have less rigidty than Stock or Street compound. Increased tire pressure compensates for lower level of rigidity of softer compounds.
There is no need (as sometimes in FM5) to have different tire pressures for front and rear wheels. From my experience this will always create a slight imbalance (over- or understeer). Fine tuning over- and understeer should be done with
–>ARBs,
–>Springs and
–>Dampers.
Keep in my mind that the series tire compound may not be Stock compound for all cars. For most race cars the series tire compound is Race compound (only Drag compound is available as upgrade), likewise for some sports cars the series tire compound is Sport compound (only Race and Drag compound available as upgrade). Set the tire pressures accordingly.
Note: This method will provide peak tire performance starting 3rd lap for average sized race tracks, the first two laps are needed to warm-up the tires.
CamberCamber settings are car type specific. As a general rule of thumb: older cars require less static camber because the more flexible chassis / suspension creates more dynamic camber. Modern cars with more rigid chassis / suspension can be run with higher camber. However due to very high forces during cornering for gp race and prototype race cars its the other way around: older gp and prototype race cars require higher camber than modern gp and prototype race cars.
Static Camber should be set so that the (dynamic) Camber on the apex when you start accelerating out of a turn is around 0 to maximize tire contact patch which in turn provides maximum tire grip. This is especially important for the driven wheels.
Front camber is usually higher than rear.
Also generally AWD and FWD cars require more camber than RWD cars to combat inherent understeer.
Usual ranges:
- older cars: -1.5 to -0.5
- modern cars: -2.5 to -1.5
- older gp race cars: -3.0 to -1.0
- modern gp and prototype race cars: -1.5 to -0.5
Keep in my mind that tire width directly influence camber settings:
- Increase tire width: reduce camber; decrease tire width: increase camber --> this is due to wider tires increase contact patch, so for optimal grip camber needs to be reduced as well.
ToeI usually don't touch toe as this from my experience creates almost always unwanted imbalance during turning.
The only exception is that I use rear toe-in (max. -0.3) for production cars with high
–>Caster (>=6.0) as I find this improves accelerating out of turns, i.e. reduces on-throttle understeer.
CasterCaster is also a car type specific setting. As a general rule of thumb older cars require higher caster than modern cars and race cars requiring lower caster than production cars. However due to high forces during cornering GP race cars and prototype races cars generally need high caster that provides extra stability during cornering.
Each car has a "natural" caster that suits the cars suspension geometry best. You wont unlock the full potential of a car when the caster is not set to the cars natural caster.
Usual ranges:
- very old production cars 7.0
- older production cars & muscle cars: 6.0
- modern production cars & older race cars: 5.0
- modern race cars: 4.0
- prototype race cars: 5.0-6.0
- older gp cars: 7.0
- modern gp cars: 6.0
Higher caster creates turn-in resistance (off-throttle understeer) while lower caster reduces turn-in resistance (off-throttle oversteer).
Older cars benefit from more turn-in resistance (i.e. high caster) whereas race cars are held back with too much turn-in resistance.
ARBsARB setttings have a direct relation to chassis stiffness and vehicle weight, i.e. the more rigid the chassis is the lower the ARBs can be set. Likewise the less the car weights the lower the ARBs can be set.
20 is good middle ground for modern production cars around 3000lbs. Increase ARBs for cars with more weight and / or less rigid chassis (e.g. older cars). Decrease ARBs for cars with less weight and / or more rigid chassis (e.g. race cars). However due to high forces during cornering gp race cars and prototype race cars require higher ARBs in relation to weight than other cars to provide extra stability during cornering.
Front and rear ARB distribution has a relation to weight distribution, so in general a car with more front weight should have also higher front ARBs than rear. This is however not as simple as 1:1 distribution according to weight distribution because springs and dampers also affect car balance during turning.
A good starting point for ARB distribution for RWD cars is 1 per 1% weight distribution, i.e. for 51% front weight distribution the front ARB should be 1 higher than rear ARB. Older cars and muscle cars require higher spread (>1 per 1%) while race cars require lower spread.
==> Example: ARBs for a modern production car with 3000lbs @ 51% wd would be: Front: 20 + 1/2 = 20.5 and Rear: 20 - 1/2 = 19.5.
The same applies to AWD and FWD cars but they generally require a lower spread than RWD cars to combat inherent understeer.
Keep in my mind that adding chassis reinforcement upgrade increases chassis rigidity, i.e. ARBs should be reduced accordingly.
SpringsSpring rates have a direct relation to car weight, weight distribution and chassis / suspension stiffness. More weight requires stiffer springs and more flexible chassis / suspension require higher spring rates on the non driven wheels (front for RWD) and lower spring rates on driven wheels (rear for RWD).
Distribution of front and rear spring rates is influenced by weight distribution, so cars with more front weight will require also higher front spring rates. As with ARBs this is not a simple 1:1 distribution according to weight distribution as for instance the drive wheels are usually run with lower springs rates in relation to non driven wheels to reduce wheel spin.
As others suggested a good range is between 1/3 and 1/2 of the slider though there are exceptions where you need to run above or below that range.
These are the ranges for spring rates I usually operate (given in percentage of distributed front / rear weight):
RWD/AWD:
Front Springs: 95%-90%-80%-50% (old car --> modern car --> race car --> gp car)
Rear Springs: 50%-80%-85%-95% (old car --> modern car --> race car --> gp car)
FWD:
Front Springs: 50%-80%-90% (old car --> modern car --> race car)
Rear Springs: 95%-90%-80% (old car --> modern car --> race car)
==> Example: front spring rate for a modern RWD car with 3000lbs @ 52% wd would be 3000 / 2 * 52% * 90% = 702lbs
As with ARBs keep in my mind that adding chassis reinforcement upgrade increases chassis rigidity, i.e. spring rates should be reduced accordingly.
Also when adding
–>Aero spring rates need to be increased to compensate for added downforce, this is usually in the range of 0-5 lbs depending on amount of added downforce.
Similarly when increasing tire width spring rates need to be increased as well to compensate for added grip. This is usually in the range of 0-5 lbs depending on increased tire width.
Ride HeightRide height works as an additional stabilizing factor like aero and a higher ride height generally allows you to brake and turn faster. However raising ride height also raises the center of mass which hurts turning. So there is a sweet spot for each car which I call optimal ride height.
In general for older cars the optimal ride height is higher than for modern cars and for race cars the optimal ride height is lower than for street cars.
Always keep front and rear ride height level , i.e. keep the sliders aligned. Having front and rear ride height sliders unaligned almost always creates slight imbalance during turning from my experience.
Ranges (front ride height):
Older cars: 3.5-6 inch (gp car --> street car)
Modern cars: 2.5-4 inch (gp car --> street car)
Two exceptions of this rule::
- set ride height to lowest if the front ride height can be set below 2 inches, this seems to be the faster option provided you have enough aero
- use higher ride height if you have extreme power builds that require extra stability
DampersDamping stiffness has a direct relation to chassis stiffness, i.e. a more rigid chassis requires higher overall damping stiffness. Damping stiffness is the sum of bump and rebound.
Bump has a direct relation to front car weight and suspension stiffness, i.e. the higher the cars front weight is the higher the bump is required to avoid diving on turn-in. Also cars with stiffer suspension require less bump whereas older cars with softer suspension require stiffer bump.
Rebound has a direct relation to bump and chassis stiffness, the higher the bump the lower the rebound is required and vice versa. Also the more rigid the chassis is the higher the rebound can be set.
Rebound should always be higher than Bump.
Also generally AWD and FWD cars require lower bump and higher rebound than RWD cars to combat inherent understeer.
Usual ranges (RWD):
- Production cars: Rebound: 7-8 / Bump: 4-5
- Race cars: Rebound: 8.5-9 / Bump: 4-4.5
- Prototype race cars: Rebound: 9-11 / Bump: 5-7
- GP race cars: Rebound: 9-13 / Bump: 5-9
Usual ranges (AWD/FWD):
- Production cars: Rebound: 6.5-7.5 / Bump: 3.5-4.5
- Race cars: Rebound: 8-8.5 / Bump: 3.5-4
- Prototype race cars: Rebound: 9-11 / Bump: 5-7
The relation between front and rear dampers should mirror the relation of front and rear spring percentage rates, i.e. if the front spring percentage rate is lower than the rear spring percentage rate the front dampers should also be lower than the rear dampers and vice versa.
--> Example: if front spring rate is 50% and rear spring rate is 80% the front rebound/bump should also be lower than rear rebound/bump.
The higher the difference between front and rear spring percentage rate is the higher should also the difference between front and rear dampers.
AeroOptimal Aero distribution is directly dependent on car weight distribution. The more front weight a car has the more rear aero is required in relation to front aero.
For standard Forza race aero kit equal aero distribution seems to be optimal for front weight distribution around 47%, i.e. the sliders for front and rear aero should be aligned for cars with 47% front weight distribution. For cars with front weight distribution <47% rear aero slider should be lower than front aero and for cars with front weight distribution >47% the rear aero slider should be higher than the front aero.
Optimal Aero distribution is more relevant on lower classes (E-B) where you don't always run full aero. In higher classes where you often run max aero anyway the effects are negligible.
BrakesBrake settings from my experience are user preference and not car specific. I always run 48% brake distribution with 125% brake pressure which favors trail braking. Others that don't trail brake prefer more front distribution (i.e. brake distribution>48%).
DiffDiff is for fine tuning corner entry and exit behaviour. It has a relation to chassis stiffness, i.e. cars with more flexible chassis require higher decel and lower accel, cars with more rigid chassis can be run with less decel and higher accel.
Usual ranges:
RWD: 68/35 is good middle ground for modern production cars, increase accel and/or decrease decel for cars with more rigid chassis/suspension (i.e. super cars, GT race cars etc.), decrease accel and/or increase decel for cars with more flexible chasssis/suspension
AWD: 68/0/100/70/35 is good middle ground for modern production cars, increase accel and/or decrease decel for cars with more rigid chassis/suspension, decrease accel a,d/or increase decel for cars with more flexible chassis/suspension
FWD: 48/0 is good middle ground for modern production cars, increase accel for cars with more rigid chassis/suspension, decrease accel for cars with more flexible chassis/suspension
Usual ranges (gp and prototype race cars):
RWD: 98/0 is good middle ground for modern gp and prototype race cars, decrease accel for older gp and protoype race cars
AWD: 100/0/100/0/100 is good middle ground for modern prototype race cars, decrease accel for older protoype race cars
FWD: 100/0 is good middle ground for modern prototype race cars, decrease accel for older protoype race cars
Note: for some reasons increasing and decreasing accel only works good in 2-step increments (i.e. accel should always be an even number) while for decel 1-step increments are just fine.
So these are basically the things I learned from tuning in Forza over the last 2 years. Hopefully some of the tips may help!
Fifty
Edited by user Tuesday, September 19, 2017 11:52:10 PM(UTC)
| Reason: Ride height detailed