Tuning for Oversteering & Understeering

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Understeer Corrections Oversteer Corrections
Raise front tire pressure. Lower front tire pressure.
Lower rear tire pressure. Raise rear tire pressure.
Soften front shocks. Stiffen Bump. Stiffen front shocks.
Stiffen rear shocks. Soften rear shocks.
Lower front end. Raise front end.
Raise rear end. Lower rear end.
Widen front track. Reduce rear track.
Install shorter front tires. Install taller front tires.
Install taller rear tires. Install shorter rear tires.
Install wider front tires. Install narrower front tires.
Install narrower rear tires. Install wider rear tires.
Soften front sway bar. Stiffen front sway bar.
Stiffen rear sway bar. Soften rear sway bar.
More front toe out. More front toe in.
Reduce rear toe in slightly. Increase rear toe in.
Increase front negative camber. Reduce front negative camber.
Increase positive caster. Reduce positive caster.
Soften front springs. Stiffen front springs.
Stiffen rear springs. Soften rear springs.
May need more front suspension travel. May need more rear suspension travel.
Install wider front wheels. Install wider rear wheels.
Use softer front compound if possible. Use harder front compound if possible.
Use harder rear compound if possible. Use softer rear compound if possible.
Remove weight from front of vehicle. Add weight to front of vehicle.
Add weight to rear of vehicle. Remove weight from rear of vehicle.
Drive a different line. Driver may be going in too deep.
Use weight transfer to your advantage. Driver may be getting on the throttle to early.
High Speed. Increase front wing downforce. High Speed. Increase rear wing downforce.
Vehicle is TWITCHY at limit and hard to keep ahead of in the steering department. Vehicle slides and is easy to drive at limit but does not corner to full potential.
Lower front and rear tire pressures slightly. Raise front and rear tire pressures slightly.
Suspension may be too stiff. Suspension may be too soft.
Shocks may be set too firm. Shocks may be too soft.
Tires may be old or hard. Roll centers may be too high.
Vehicle may not have enough suspension travel. Lower vehicle.
Vehicle may have a toe problem front or rear. Tires may be too hard.
Increase negative camber front and rear if possible. Widen track front & rear.
Raise front tire pressure. Lower front tire pressure.
A properly set up vehicle will usually push slightly on corner entry, be fairly neutral at the apex (STEADY STATE) and exhibit slight power oversteer on corner exit. Tight courses may require more oversteer, fast tracks more understeer.
Items needed:  Accurate tire pyrometer, tire gauge, tape measure, and a logbook. Suspension information books.
Note: This is a sample of the methods used to correct various handling problems. Books have been written on this subject. Not every correction will always work as expected. Stiffer front sway bars will in many cases will decrease understeer because of decreased body roll and better camber control. The best rule is to change only one thing at a time and keep notes. Shock adjustments typically will have the greatest effect on corner entry and exit.