General Tips on How To Tune:
There are some links to fully featured guides on tuning at the source, but here we will focus on some general advice.
Overall, you will want to improve handling before power. You don’t need more power if handling isn’t at its best yet. For this reason, auto tuning is actually terrible in this game.
Fix the end of the car with the problem. You won’t be able to fix problems with rear sliding by adjusting the front. Stabilize the rear, and then adjust both sides to stiffen or soften appropriately.
Add every handling part except weight reduction, and also a race differential. All these handling parts are essential.
Add aero to A or S class cars, don’t add them for C or D class cars. With B class cars, adding aero is 50/50.
If you’re starting out, look at Recommended Tunes, and check what stats you have vs what you need to change.
Here’s an order for upgrades recommended by one fan: engine cam, exhaust, and air filter.
When tuning transmission, you will want to be able to adjust the final drive. This way, you can set acceleration for short tracks and top speed for tracks with long straights. When you’ve gotten good at it, you can switch to racing transmission, with three to four speeds.
The differential may be the most important part in high end sports cars.
For handling, do everything that doesn’t raise the PI much before anything else. Squeeze as much handling out of it as you can.
How To Wheelie Tune:
Wheelies are easier to pull off in Forza 5 compared to its predecessor. For this example, we’re using the RUF Yellowbird.
Do not change the stock engine, but get all the possible engine upgrades. When you’re done, you will then want to do the same for the brakes. Add race suspension, front and rear roll bys. Do not add a roll cage. You will want to upgrade all the parts on the drivetrain, including clutch transmission, driveline and differential. Finally, use drag tyres front, and use the widest tires available on the rear.
Now, when it comes to tuning, you want to raise the front tyre pressure up and the rear tyre pressure down as much as possible. This will give you more traction and better power, instead of wheelspin. For forward gears, you set Final Drive at 4.3 and 1st at 2.5. For the camber and toe, put front and rear at zero degrees, and front caster at maximum. For the anti-roll bars, raise front and rear to maximum.
For the springs, front tires should be as soft as possible, and rear tires as stiff as possible. For the ride height, front and rear should both be raised to the maximum. For rebound and bump stiffness, front should be as soft as possible, and rear as stiff as possible. For braking force, balance needs to bet set at 20 % at rear, and pressure at maximum. You can check out gameplay of this setup below.