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Ranger Mike
#335
Mar12-12, 04:42 AM
Sci Advisor
PF Gold
P: 1,468
smokin..
some notes on wheel hop

you said When straight line braking , such as in road racing whatstops wheel hop or rear wheel lock up with out dialing all front brake in.


Rear wheel hop is basically the suspension gets into a resonant situation and doesn't dampen itself out.

Under acceleration, the rear suspension compresses. Due to inertia, the wheel continues traveling upward. This unloads the tire, reducing the acceleration force. The spring then pushes back down on the wheel, and it regains traction, forcing the wheel back up.


Play and movement in suspension arms can exaggerate the problem.

The best way to fix it depends on the vehicle. Vehicles suspension can be designed with "anti-squat" capabilities, but at the expense of ride quality. 4 link cars with solid rear axles can use "no hop" bars to change the suspension geometry.

Angle of upper link on rear end will effect wheel hop. A large amount of anti squat ( down hill angel of top link) will cause rear end lightness and rear wheel hop under braking. The 3rd link shock will effect it as well.
Shocks, shocks shocks..check the shocks...stiffer shocks will help.


Leaf spring cars can use traction bars to eliminate it.

is there any rear measurements that can be adjusted to stop so much weight transfer to the front when braking , or be able to make the whole car lower during braking

Stiffer ARB ( sway bar). Softer rear spring package. Need to keep more weight on rear end.

Also, test the car with a light fuel load because the weight difference (sometimes in the neighborhood of 150 pounds) can affect wheel hop as well. Wheel hop is less likely on production-based sports cars with an independent rear suspension because the center- section of the axle is hung by the chassis, but it can still occur especially if an unskilled driver is punching the brakes and shifting the gears