scrub radius and rears....easy and fun question

[Jonny Hotnuts]

We had wheels made for our rears with a 3" backset on a 3.5'" wheel on our old setup. This is to push the wheels as far under the car as possible and was because or Rx7 rear end assembly was for a wider vehicle then our Fiat. Most of what I understand with scrub radius is that is pertains to the front or steering wheels.

My question is that will having my backset on my rears pushing the contact patch so far under the car will this negatively affect handling?

We are having new wheels made for our 5 lug hubs and was wondering if I should get less backset and increase Fa for improved handling.

~JH

[dw230]

Why would you want to put the tires under the car at the rear? Conventional wisdom says that the tires should be at the outer edges of the fender wells.

DW

[Jonny Hotnuts]

Why would you want to put the tires under the car at the rear? Conventional wisdom says that the tires should be at the outer edges of the fender wells.

DW

Because if I were to use the standard backset for the Rx7 the tires would be sticking out 4" on each side (*this would be if I were to also use the 5" tires the Mazda uses)

Because I am using a more narrow tire and high backset this keeps my rear tires very close to the body line.

I want them flush, and they are really close now....but I dont know if the high backset could be causing problems.

[Peter Jack]

Only if the wheels or axle housing are flexing Jonny.

Pete

[John Burk]

Before top fuel dragsters used full floating read hubs the large scrub made the slicks toe in under power which helped handling . LSR cars wouldn't get that with smaller Gs and scrub .

[Jonny Hotnuts]

Got it....

Thanks for the replies!

~JH