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analogkid455
03-04-2007, 04:18 PM
I had a 2nd gen F-body and wanted better handling. I suggested to my local speed shop that I need a stiffer front end and he said the opposite. So, I asked if I took the front anti-roll bar off, would it have less understeer? He said yes! Is he right? He also said that drag racers like stiffer front ends and softer rearends for better weight transfer. I have always found the opposite in practice. Am I delusional?

David Pozzi
03-04-2007, 07:26 PM
It's not allways that simple but if you are talking about front to rear cornering balance, then softening the front will induce oversteer, stiffening the front in roll will induce understeer.

I'm not up on what drag racers do but hear about rear anti-roll bars they use.

Depending on how much better you want the car to handle, the first step would be front and rear antiroll bars that are larger. Then stiffer F/R springs and better shocks.
Global West and Hotchkis have some good spring and bar kits that are balanced to work together. Tubular upper arms should be used to achieve aprox 5 deg positive caster which really helps keep the tire flat in a turn.

We autocross a 73 Camaro and started with the Hotchkis TVS system. The only problems with the kit was the rear leafs were a bit too low, and the special Hotchkis supplied Bilstein shocks were on the soft side for use with autocross slicks. But not bad on the street.

Slow Ride
03-04-2007, 08:22 PM
That guy is full of it. For a drag car you want the front to be soft with a tall spring to store lots of energy and shock that is weak on extension and stiff on compression to let, so when you stab the gas all of the energy in the springs is released. In the rear you want it to be somewhat stiff to plant the tires with the energy being transfered from the front. Anti-roll bars for the rearend make the car leave straight since it helps to plant the drivers rear, counteracting the engines torque.

As for the balance of a street car/handling car. I would think that you woulks have less understeer with a lighter spring rate and approriate shock damping. Removing your anti-roll bar will make the car fell like a boat and it will lean too much on curves. Maybe changing the diameter of the front bar or adding a rear would help and still keep the same comfort level on the highway.

Derek69SS
03-05-2007, 10:05 AM
Do stock 2nd gens have a backward camber curve like the earlier cars? If so, I would think a bigger sta-bar/more roll stiffness would actually help reduce the understeer by helping to keep the tire contact patch flat on the road surface.

Norm Peterson
03-05-2007, 11:09 AM
It's going to give both effects in all cases. The smaller amount of lateral load transfer occurring up front from a smaller bar or none at all is an oversteer effect (assuming no other changes). The resulting greater camber change (loss) is an understeer effect. Whether the overall effect will be understeer or oversteer depends on the rest of the vehicle set-up. Roll center heights, suspension geometry and motion ratios, spring stiffnesses, etc., will all affect what happens when you change the front sta-bar stiffness.

If the only change made is to reduce or eliminate the front bar, the car will be a little slower to take a set, as this reduces the frequency in roll (the quarter-cycle from zero roll to the steady-state roll position will take a little longer to happen).


Norm

Goatman
03-05-2007, 03:59 PM
Drag racing:

You want the spring and shock to extend without much inital effort to aid in wieght transfer. But you also want it to come back down before the car starts going fast.


Stay out of speedshops. I've never found one to be of any usefull information....