Solving Handling Problems

[ConeDodger]

The key to setting up your suspension is in diagnosing what the handling problems are and resolving how to fix them. While car enthusiasts often baulk at the "black art" of suspension tuning, there's no reason to. As with working on the mechanical aspects of an engine, the trick to suspension tuning is in the troubleshooting; there is always a cause and an effect.

Steady state understeer
All turns or low-speed turns only
If front tire temps are optimum and rears are low, stiffen rear antiroll bar; if front temps are too hot, soften front (most likely).
If front tire pressures are optimum, decrease rear tire pressure. Increase if chunking occurs.
Improper front camber.
Too much body roll at front, causing excessive camber change.

Steady state understeer
High-speed turns only
If front tire temps are OK, increase front downforce.
If front tire temps are too hot, reduce rear downforce.

Steady state oversteer
All turns or low-speed turns only
If rear tire temps are optimum, with fronts too low, stiffen front antiroll bar; if rear temps are too hot, soften rear antiroll bar (most likely).
If rear tire pressures are optimum, decrease front tire pressure. Increase if chunking occurs.
Improper rear camber.

Steady state oversteer
High-speed turns only
If rear tire temps are OK, increase rear downforce.
If rear tire temps are too hot, reduce front downforce.

Corner entry understeer
Front shocks are too soft in bump resistance.
Too much front toe-in; use a small amount of front toe-out.

Corner exit understeer
Rear shocks are too soft in bump.
Front shocks are too stiff in rebound.

Corner entry oversteer
Rear shocks are too soft in rebound.
Rear ride height is too high (too much rake) compared to front.

Corner exit oversteer
Rear shocks are too soft in rebound.
Too much rear toe-in or any rear toe-out.

Straightline instability
Tire pressure is too low in one or more tires.
Too little positive front caster.
Too much front toe-in or any toe-out in rear.

Straightline speed too slow
Too much overall downforce.
Too much toe-in or toe-out.
Ride height is too hight.

Excessive steering effort
All turns
Too much positive caster.

Chassis or suspension bottoms
Spring rates are too soft.
Shock absorber bump rates are too soft.
Inadequate suspension travel.
Inadequate ride height.
Front tire pressures are too low.