Editing Automobile handling (section)

== Aftermarket modifications and adjustments ==
{{Main|Racing setup}}
{{Unreferenced section|date=November 2008}}
Lowering the center of gravity will always help the handling (as well as reduce the chance of roll-over). This can be done to some extent by using plastic windows (or none) and light roof, hood (bonnet) and trunk (boot) lid materials, by reducing the ground clearance, etc. Increasing the track with "reversed" wheels will have a similar effect, but the wider the car the less spare room it has on the road and the farther it may have to swerve to miss an obstacle.

Stiffer springs and/or shocks, both front and rear, will generally improve handling on close to perfect surfaces, while worsening handling on less-than-perfect road conditions by "skipping" the car (and destroying grip), thus making handling the vehicle difficult. Aftermarket performance suspension kits are usually readily available.

Lighter (mostly aluminum or magnesium alloy) wheels improve handling as well as ride comfort, by lessening unsprung weight.

Moment of inertia can be reduced by using lighter bumpers and wings (fenders), or none at all.

Fixing understeer or oversteer conditions is achieved by either an increase or decrease in grip on the front or rear axles. If the front axle has more grip than a similar vehicle with neutral steer characteristics, the vehicle will oversteer. The oversteering vehicle may be "tuned" by hopefully increasing rear axle grip, or alternatively by reducing front axle grip. The opposite is true for an understeering vehicle (rear axle has excess grip, fixed by increasing front grip or reducing rear grip). The following actions will have the tendency to "increase the grip" of an axle. Increasing moment arm distance to cg, reducing lateral load transfer (softening shocks, softening sway bars, increasing track width), increasing tire contact patch size, increasing the longitudinal load transfer to that axle, and decreasing tire pressure.

{| border="1" style="width:600px; border-collapse:collapse" cellspacing="0" cellpadding="5"
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! style="background:#cce;"| Component
! style="background:#cce;"| Reduce Under-steer
! style="background:#cce;"| Reduce Over-steer
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| Weight distribution || [[center of gravity]] towards rear || center of gravity towards front
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| Front [[shock absorber]] || softer || stiffer
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| Rear shock absorber || stiffer || softer
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| Front [[sway bar]] || softer || stiffer
|-
| Rear sway bar || stiffer || softer
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| Front [[tire]] selection<sup>1</sup> || larger [[Contact patch|contact area]]² || smaller contact area
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| Rear tire selection || smaller contact area || larger contact area²
|-
| Front wheel rim width || larger² || smaller
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| Rear wheel rim width || smaller || larger²
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| Front tire pressure || lower pressure || higher pressure
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| Rear tire pressure || higher pressure || lower pressure
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| Front wheel [[Camber angle|camber]] || increase negative camber || reduce negative camber
|-
| Rear wheel camber || reduce negative camber || increase negative camber
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| Rear [[Spoiler (automotive)|spoiler]] || smaller || larger
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| Front height (because these <br>usually affect camber <br>and roll resistance) || lower front end || raise front end
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| Rear height || raise rear end || lower rear end
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| Front [[toe (automotive)|toe]] in || decrease || increase
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| Rear toe in || decrease || increase
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| colspan="3" style="background:#eee;"| 1) Tire contact area can be increased by using tires with fewer grooves in the tread pattern. Of course fewer grooves has the opposite effect in wet weather or other poor road conditions.

2) Considering same tire width, and up to a point for the tire width.
|}