Autocrosses (at least those sanctioned by SCCA and NASA) are designed to keep vehicle speeds no higher than what people normally experience driving on the highways (65 mph). And those speeds are usually achieved on the longest straight. Corner speeds are generally 50 mph and under.
The only wings that would be effective at that speed are very large sprint car type wings with a huge surface area. Basically something that has much surface area as the roof of the car. A simple spoiler or wing over the back of the truck is only decorative at autocross speeds.
Mechanical (not Aero) changes are really the only way to achieve increases in grip for most full bodied vehicles at autocrosses.
Adding weight to any race vehicle, unless required by the rules, is a bad thing - except in some very rare circumstances where you can't correct a handling problem through more traditional tuning techniques.
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John Coffey
johnc@betamotorsports.com
