Front to Rear Tire Size Ratio

[DocDirk]

So as I understand it...it's too simplistic to say that any given set of tires must have a front to rear ratio to perform well... the jist of what I'd been told was that going to 335's on the rear would cause the car to "push" in turns, wanting to go straighter than a smaller rear tire would. I see your point on diameters, Larry, thanks. I'm just wondering if I could increase the rears to 335 for straight line traction and (given the identical setup) not cause a net loss of decent street cornering manners.... and yes, I understand no such question has a simple answer!

Thanks and ride safely

Dirk

[Larry N Johnson]

Originally Posted by DocDirk

So as I understand it...it's too simplistic to say that any given set of tires must have a front to rear ratio to perform well... the jist of what I'd been told was that going to 335's on the rear would cause the car to "push" in turns, wanting to go straighter than a smaller rear tire would. I see your point on diameters, Larry, thanks. I'm just wondering if I could increase the rears to 335 for straight line traction and (given the identical setup) not cause a net loss of decent street cornering manners.... and yes, I understand no such question has a simple answer!

Thanks and ride safely

Dirk

If your roadster will fit 335's and it will help straight line traction and accelleration, then go for it. Here is an example of a 325/50x15 tire drag racing in an SPF:

Greg Schroeder from Scottsdale, AZ says

easy start video
10.91 @ 128.75 pass

- What gear ratio is yours?
Ford 8.8 3.73 with Detroit Truetrac, Tremec TKO 600 and the tires for drag racing are Mickey Thompson ET Street Drag radials, 325/50 15, actual height 27 inches tall.


- What engine?
Roush 427R-095 with single plane intake manifold
Switched carb to Pro-Systems 1000 cfm double pumper
switched to 2 inch primary headers
switched to Buckshot Racefab side pipes

- Total weight?
race weight should be 2550lbs with me in the car and gas.

My SPF number is 2040. Mine was one of the last ones with the Ford 8.8 3.73. I'm not sure exactly which number car they switched, but the new SPF cars come with a Dana rear end which I believe is the same type in a new Pontiac GTO.

[DocDirk]

Thanks for the replies! I don't know enough about performance automobiles .... but I'm finding out more! Just got my Vehicle ID # from California CHP, next it's off to BAR and DMV next week....fingers are crossed! Would a rank amateur performance car driver be able to tell any difference between 295 rear tires and 335's? Or is that more the kind of difference one only notices at the extremes of performance demands such as road racing or drag racing? I'll be heading up to Infineon Raceway for driving school when all the mechanical kinks have been worked out, but for the first few weeks I'll just be getting used to the toy

Might be legally drivable in less than a week! Oboyoboyoboyoboyoboy!!

Dirk