Help with tuning (updated)

Hi to all

I am looking for anyone to test out a tune i have for the 97 nissan r33 gtr

I like the slight oversteer my tune creates, but i’m getting problems with huge understeer both on accel and decel, seems to be any type of corner, slow fast etc

Any and all help is much appreciated. I play on xbox one x with a controller.

Car has stock engine with every race upgrade installed, apart from the sport rollcage, widest wheels/extended wheel spacing etc

What i have so far is as follows

S2 903, 672hp, 541 torque, 2742lb’s weight, 54% distribution, 4wd

Tyres: 28psi front and rear
Gearing: fd 3.60, 1st 3.30, 2nd 2.08, 3rd 1.51, 4th 1.19, 5th 0.98, 6th 0.83
Alignment: camber -1.9 front -1.9 rear, toe 0.0 front and rear, caster 4.9
ARB’s: 21.37 front 14.27 rear
Springs: 660.5 front 562.6 rear, ride height 5.8 front and rear
Damping: rebound 8.5 front 6.8 rear, bump 4.2 front 4.3 rear
Aero: locked (full jun body kit)
Brakes: balance 48%, presure 140%
Diff: front 55% accel 0% decel, rear 84% accel 74% decel, centre 80% balance.

Try this:
Camber -. 5 rear
Caster - 5.5
Brakes 55% (for oversteer on braking)
Front diff accel 45%
Read accel 75, decel 65
Should be able to keep balance around 70.

If that doesn’t work, continue to lower front diff, soften front sway/springs, stiffen rear sway/springs. Maybe lower rear diff slightly as well probably as a last resort.
Your current settings definitely understeer. Don’t need to drive it :slight_smile:
Front bump damping is also too low. Should check telemetry - you’re probably bottoming out under load.

Most vehicles dont do well with fully upgraded everything. This is too far from the natural class the vehicle is in. Thats likely your oversteer problem. Understeer is likely in your tune.try increasing rebound to around 10.5 ish and lower the bump to around 1-2. increase camber to around 2.5 and also increase caster to around 5.5.

These settings worked pretty well for me (assuming race tires which you didn’t specifically mention, your build was S2 902 for me):
Tire pressure 29.0 29.0
Camber -1.8 -1.8
Toe 0.0 0.0
Caster 5.0
Anti-roll bar 17.87 16.07
Springs 579.5 514.7
Ride height 5.0 5.0
Rebound 12.9 12.6
Bump 4.8 4.6
Brakes 52% 125%
Diff front 74% 0%
Diff rear 100% 74%
Diff distribution 75%

Values are straight out of QuickTune H4 btw.

1 Like

I’m definitely going to get QuickTune H4, I loved QuickTune 7 so it’s on my priority shopping list.

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Forza isnt’t quite real life, I’d be majorly understeering with about all of these combos. With these kinds of AWD cars, I like the front a lot freer and the rear end a lot stiffer. In fact, if that’s for road use, trying to race not tour, I’d want more front spring, too. Especially with all the grip in the game.

Anti-roll bars at around 6.00/16.00 f/r

Front springs at 900, rear between 1000 and 1050 … and, honestly, probably closer to 1050.

Diff acceleration 28/0
Diff decceleration 80/75

Balance … I do this last at try to find the sweet spot where acceleration is maximized. Cars just like it, for handling, too. For this kind of car, it’ll probably be between 60-68. Probably closer to 60. Unless there’s a completely clear sweet spot out of that range, i’d try to keep a R33 in this range.

For the record, I front-paged more than a dozen leaderboards in FH3, and the only rival event I messed with since the first week or so is the B class retro saloons and I’m #10 right now in what I think is a slower car than anybody above me was in. This stuff works.

I used to tune based on what I thought was more realistic, with values more like you guys, but that only got me so far in the game. Never felt right, wasn’t faster. This is where it evolved to. When I get a tune just right, I can really feel it.

Another tip to finetune understeer if you are playing with a controller is to drive the highway full blast and see how nose-y the car is with small steering inputs. If the nose seems to do too much, you’re understeering. When you get this balance perfect on the highway, it’ll translate to road courses. If you get it just right, you’ll know it.

So i have been reading through the replies and took all advice on board. Thanks for the help!
Ive basically just tried mashing things together and tweaking little bits.

Here is what is changed from original tune.

Alignment: camber -2.5 front 0.5 rear, caster 5.5.
ARB’s: 6.00 front 16.07 rear.
Springs: 900 front 1050 rear.
Damping: rebound 10.0 front 8.3 rear, bump 6.7 front 6.8 rear.
Brakes: 55%
Diff: front 28% 0% rear 80% 75% centre 60%

Things do now feel more controllable, understeer is still there, albeit a lot less, gained more off throttle oversteer but it is manageable. Just need to fine tune really. Any more help as always is much appreciated!

Than you need to increase decel dif. This solely adjusts off throttle balance

While all of it has been some good advice, I would have taken a different approach. I would have evened out the car’s weight distribution to keep the car from rolling it’s weight from one side or the other. I have a tuning calculator that will actually do this for me. As far as over/under steering, there is one setting I have not seen mentioned yet, which is under the differential you can change the power between the front and the rear. to help a car turn a bit more into a corner I would actually give the rear end more power over the front end. The reason is because on FWD and AWD vehicles, you will get what’s commonly refer to as torque pull, which is the torque of power in front wheels causes the car to “pull” in the direction of the wheels and often the car will want to straiten out. So no matter what you do with the Camber or Toe, the car will just not turn. So I would try evening out my car’s weight and change the power to a bit more to the rear over the front to try and help this. Here’s a link to my tuning calculator to help even out the car’s weight.

I missed that part about the body kit you used. Sorry about that. It changed things a little bit because without all that downforce, you can’t run with as much rear spring.

I played around with this car last night, and I couldn’t exactly match your build either, but it was close enough I think. It wasn’t easy to tune and I think it still needs some fine tuning, but I took it to a couple circuit races and the times were pretty respectable. S2 902 is maybe 20 or so added pounds from being an S1 car, which is probably about 1 or 2 tenths of a second on a circuit … so it’s pretty close to being an S1 car.

At Moorhead Wind Farm Circuit, it ran about 40 seconds flat, which is pretty good for an S1 car, especially without adjustable aero. It kicks the tail of the new Corvette ZR1 by about 0.5 seconds.

At Bamburgh Circuit, it ran 51.5’s. Without aero, that’s pretty impressive. Getting under 50 seconds there is really doing something, even in the best car in class with adjustable aero.

Here’s the tune:

29.0/29.0 … f/r
I used your gearing from the original post.
Alignment: camber -1.6 front -1.0 rear, toe 0.0 front and rear, caster 5.2
ARB’s: 6.07 front 16.07 rear
Springs: 951.5 front 1051.7 rear, ride height 5.2 front and rear
Damping: rebound 9.2 front 10.6 rear, bump 4.0 front 4.7 rear
Brakes: balance 50%, presure 80%
Diff: front 28% accel 0% decel, rear 80% accel 75% decel, centre 66% balance.

I played with the springs a lot and getting about 100.0 difference between front and rear was just coincidence. A lot of trial and error. I think the springs are good, but where I’d fine tune would probably be the in the differential. I didn’t seem to bottom out anywhere, either. If it’s for asphalt use, I might drop it all the way down to 5.0/5.0.

Not sure if I should comment given the other settings mentioned.

Lower deceleration diff to close to zero.

Lower front anti roll bars to near 10.