OK, having read MANY threads on tire width versus traction, people seem to be split on how much it helps to have a wider tire. I know that some say going from a 275/35/18 to a 285/30/18 actually causes a LOSS in traction!!

So heres my question:

For a 20B powered FC3S, you will obviously need as much traction as possible. Given the use of fender changes, it would be possible to get a wider tire in the back than normally would allow. Looking over tires, i see that there are g-Force T/A 's availiable in 2 sizes that might suit such a beastly engine. They are...

275 / 35 - 18
315 / 30 - 18

Both of these are very close in outside diameter and therefore would be probably the best choices. So, would going to that huge 315 be traction loss, or would it be a good idea on a high HP 20B (500 whp, plenty of torque) to have that big tire in the rear?

Thanks for your input!!

 

The loss of straightline traction is due to the shorter, presumably stiffer sidewall. If the sidewall height is the same -- 275/35 vs 315/30, then the wider tire should have the advantage. That is assuming that you can actually fit a 315 in the rear of a widebody FC.

 

I was going to say the same thing.

 

if you haven't driven a street ported 20b fc/fd w the boost at 10 psi+ you will not be prepared for the need for more traction.

if you dial the boost down to 5-8 psi you can get along w 275/285.

once you get used to the car you will be doing some highly motivated engineering to get the rear hooked up.

it is a beast and not to be trusted in 4th gear until your tires have a 3 handle on them.

howard coleman

 

Im confused howard, are you saying that because i havent driven a 20b fc that i wont need a wide tire? Maybe im just not reading it right...

Im really not looking for any more than 500hp at the wheels, although that is still an INSANE number. Since i like to plan out projects, i want to know IF i could fit a 315 would it be a wise thing to do? I say this because i dont want to drop $$$ on nice wheels and not have them be wide enough for the car.

Im not planning this as a drag car. Its a street car and i dont really plan to drag it. I want a stupid fast street car that wont randomly break loose due to insufficient tires (granted i know that its going to want to do this regardless). Ive been in 400hp 2 rotor cars and although they are really fast, i just dont feel that they are enough for me. I was planning 10psi normal with a 15psi high setting (probably wont be used that often) using a GT40R turbo.

I agree that a 20b is a beast that must be respected or it will bite you hard. So do you still think 315 is worth trying for given my proposed goals?

Thanks for your help so far!