Why not got 9" wheels all around on a Caarrera?

[bigrubberjeep]

Just curious since I see so many people going with 9's in the front and 11's in the rear.

[Jack Olsen]

Because there's more weight to control in the back.

[bigrubberjeep]

Wouldnt it be concidered an upgrade to the front though?

Bigger ain't always better.

[Drago]

Originally posted by Mark Wilson
Bigger ain't always better.

Unless we're talkin' R-eolas...

[Bill Verburg]

First the only Carrera that can fit a 9 in the front is a widybody. So that lets out most of them

Second, if you want to A/X and desire a lot of oversteer it might be a good idea

Third, for street, looks are big, 9s would look odd w/o the big spacers the factory uses. They wil look odd anyway w/ the same sizex f/r

fourth, for track use a 911 has oversteer at speed, this needs to be tamed, a bigger rear is a very good way to do that.

all street 911s untill the '73 RS used the same size all around, as they became more powerfull the oversteer at speed became more of a problem, so all the higher power cars since '73 have used bigger wheels and tires in the back.

[sammyg2]

It's all about balance.
60% of the weight is in the rear, you need 60% of the traction in the rear for a balanced neutral car. Obviously the car's handling is affected by weight transfer, but the point still remains.
Then there's the fact that the rear fenders on a carrera are designed for wider tires and wheels than the front..............
you couldn't fit 9" on the front and if you had the same size on the front as the back it wouldn't look right or handle right.

The very early cars got away with having the same size tires front and back to some extent because they were much lighter.

7's in the front is about the most you can fit, you can get 8's in the back easily, and 9's if the offset and tire size is right.

[bigrubberjeep]

Originally posted by Bill Verburg
First the only Carrera that can fit a 9 in the front is a widybody. So that lets out most of them

Second, if you want to A/X and desire a lot of oversteer it might be a good idea

Third, for street, looks are big, 9s would look odd w/o the big spacers the factory uses. They wil look odd anyway w/ the same sizex f/r

fourth, for track use a 911 has oversteer at speed, this needs to be tamed, a bigger rear is a very good way to do that.

all street 911s untill the '73 RS used the same size all around, as they became more powerfull the oversteer at speed became more of a problem, so all the higher power cars since '73 have used bigger wheels and tires in the back.

I have a FTL so yes to the widebody-
I do some track days up at willow and a couple A/X also-

I understand why they use large wheels in the rear (I have seen a few spins) however I don't understand why not increase the fronts to the same size?

Would this "Increase" my car's tendency to spin?

[Bill Verburg]

Would this "Increase" my car's tendency to spin?

yes, increasing the front and or decreaing the rear will increase oversteer, the tendancy to rotate about a vertical axis through the CoM

[ted]

I had success with 9 inch wide, 23 inch tall cantilevers slicks all the way around.
Adjust sway bars to suit.
Great short track set up IMHO.
Lower CG, lower final drive ratio, lower lap times and greater slip angels = fun.
Saved me 2 seconds a lap over Victoracers.
Everyday in the rain or on big tracks, nah.