Rear End Width

[George]

I'm wondering about installing the rear out of a 4thgen F-Body into my 3rd.gen.

Everything will fit except that the axle is 4 inches wider so each rear wheel will stick out 2 inches.

The car has a fair bit of suspension work and is quite comfortable around the GP track with 275/40/17s on it so I'm concerned about upsetting the present balance.

So, using the same wheels, would widening the rear as described result in oversteer or otherwise upset the car's handling.

I'm thinking it would be loose; mainly because, with karts, if they had too much grip we would widen the rear if we couldn't dial it out with increasing the air. (ie slide the hubs further out on the axle)

[thgear]

larger track width means less lateral weight transfer

or more grip before you lose traction

all else being equal, increasing your track by 4" will give the rear end more grip

the car will lean towards understeer now since the front will lose traction slightly faster

but thats just 1 variable...

[glh]

Its is opposite in a cart because of the lack of springs so you would have more grip with a wider track

[George]

Its is opposite in a cart because of the lack of springs so you would have more grip with a wider track

Yeah, they are opposites.

Widening the car and leaving the springs/shocks in the same position will increase leverage thereby decreasing the rear rate, causing more roll, less inside rear wheel lift and therefore more grip.

Widening the solid rear of the kart will cause more inside wheel lift and less grip.

Edit: I am indebted to Dean at fraxx for the above explanation.