Anyone running 225/50/R16 on 6" rims?

[cashman]

Hi,
I will be ordering tires soon and have pretty much narrowed it down to Potenza RE-11 or Dunlop Star specs for street, AutoX and DE use. I have an 89 with 6" Fronts and 8" Backs. I am very interested in putting the 245/45/R16 on the backs but wasn't sure about the fronts. The stock turbo set up per my manual states 205/55/R16 was standard for both the non turbo and turbo. Only the rear changed.

I have searched extensively and many people put the 225/50's on 7" rims. I could not find anyone running this set up on the 6" rims. (Maybe that answers my question). 6" rims technically fit the 225/50 but I am afraid it will bulge too much and effect the usefulness of the larger size.

I am not interested at this time in changing out rims so please keep responses related to the question above. 6" Fronts and 8" Backs.

Thanks for you input.

[Jesse16]

Hey cashman, very timely question. I was just doing a brake service after recent DE and did some measuring of my own on tire/rim sizes. My gut says you should be able to put the 245's on an 8" rim. I only have 7's on the back of mine with the 225's. Seems another inch of rim with 245's would be virtually the same relationship. Just feel inside the wheel well to make sure another quarter inch of rubber isn't going to rub on something. I'll need tires to start 2013 and would love a bit wider rims.

[Bill Verburg]

Tires have a design wheel width
for 225/50 x16 that design width is usually 6.0 to 8.0"

for 245/45 x16 it is usually 7.5" to 9.0"

so yes you can run them on 6" & 8" wheels respectively

but

best performance from a tire is derived when it is used on the widest possible wheel for which it is designed

best comfort from using the narrowest design wheel

[Arne2]

Two thoughts:

1.) 225/50's will be pretty pinched on 6" wheels, they're bad enough on 7". I'd probably stick with 205/55's if it were me.

2.) I thought that Bridgestone RE-11's were the only street 245/45's currently in production. Have you found a source for the Star Specs?

[cashman]

I would have to stick with the standard 205/225 set up with the star specs. The 245/45 is really tempting pending the feedback I receive here.

[cashman]

Tires have a design wheel width

for 225/50 x16 that design width is usually 6.0 to 8.0"



for 245/45 x16 it is usually 7.5" to 9.0"



so yes you can run them on 6" & 8" wheels respectively



but



best performance from a tire is derived when it is used on the widest possible wheel for which it is designed



best comfort from using the narrowest design wheel

I definitely want the best performance. So I guess the real question is which will perform better. Wider spread 205 or a pinched 225?

[flyn-hawn]

Originally Posted by cashman

I would have to stick with the standard 205/225 set up with the star specs. The 245/45 is really tempting pending the feedback I receive here.

Here is mine with 245/45 16 on 8 in rear and 225/50 16 on 7 in front

[cmpski]

Another option is a 215/55/16. It is 1.75% bigger than a 205 and the same RPM's as a 185/70/15.
A 205/55/16 is 24.88 inches and a 215/55/16 is 25.31. Give this site a try.
Tire Size Program
I wanted to go 195/60/16 on the front and 215/55/16 on the rear of my car as they are the exact same size as a 185/70/15. I could find only 1 tire made in both sizes and I didn't care for the tire. I went 195/55/16 front and 205/55-16 in the rear. I'm in a 67. You guys with the 69 and later cars have more room to play with.

[Bill Verburg]

Originally Posted by cashman

I definitely want the best performance. So I guess the real question is which will perform better. Wider spread 205 or a pinched 225?

w/ 6 & 8 I'd stay w/ 205/55 & 225/50

[DanielDudley]

Originally Posted by Bill Verburg

w/ 6 & 8 I'd stay w/ 205/55 & 225/50

Bill would know.

I think if you want to run 225/245s You want 8'' 944 turbo Fuchs in front and 9'' at the back. The 8s have a better offset for the 225 tire clearing the front fender.

[Walt Fricke]

The hot setup for SCs racing (in PCA where there are rim width limits in the stock classes) is 275x35(or something like that) on 9x15" rims. Hot due to the effective reduction of the R&P gained by the smaller diameter. Apparently this overcomes the disadvantages of mounting a tire which seems a bit too wide on that rim.

I've had good results running 225s on 7x15s in front, and 245s on 8x16s in the rear. But this is guided largely by what I have, or was able to acquire for what seemed reasonable $ 10+ years ago. For a while, 275s on 17s in the rear were favored by some, but I couldn't fit more than 245s on 9x17s I got at a bargain price.

Mind you, this experience is from track/autox use only.

[TerryHollp]

It is 1.75% bigger than a 205 and the same RPM's as a 185/70/15.