Early 911 Tire / Rim Widths

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Early 911 Tire / Rim Widths

Postby David Ray on Tue Oct 10, 2006 7:41 pm

I am trying to set up my new (old) car with the appropriate rims and rubber for this weekends performance driving school and subsequent TTs and AXs.

What is the maximum tire width that members are running on ‘67-‘71 911s with stock fenders? I have access to both 6x15s and 7x15s rims and Toyo RA-1s 205/50x15 or 225/50x15s.
Thanks
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Postby ttweed on Wed Oct 11, 2006 9:07 am

David-

The small flares on the early cars started in 1969, with the longer wheelbase tub, and remained essentially the same until the SC in 1978. The '65-68 SWB cars have no flares at all, and have different requirements than the '69-77 cars.

From your previous posts, I am assuming this is for your 1967 912? If it has a stock SWB body, I have found that the largest wheel/tire combo that can be fitted is a 205/50-15 on a stock (23mm offset) 7" rim, and you will probably have to roll the fender lips to use them. A 6" 36mm offset rim with a 205 will fit without any mods, but offers less sidewall support for the tire. You can squeeze a 225 on a SWB car in the rear with a custom offset rim, like the 911R Fuchs, but you will have to take the 2-point tire-width penalty under PCA autox/TT rules, and it may not be a legal tire for some of the Vintage racing sanctioning bodies.

HTH,
TT
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Postby Steve Grosekemper on Wed Oct 11, 2006 9:31 am

Jeez Tom!
He wants to know what to put on the car for this weekend not what can be put on the car for with $5,000 worth of modifications!

Most Early cars run 6x15 wheels.
195's work best with no issues, but 205's can usually be used with stock suspension.

7's and 225's require fender rolling, different offsets, funny alignments and stiffer suspension.
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Postby ttweed on Wed Oct 11, 2006 9:54 am

Steve Grosekemper wrote:Jeez Tom!
He wants to know what to put on the car for this weekend not what can be put on the car for with $5,000 worth of modifications!
I wasn't suggesting that he go out and buy a set of 911R wheels for the weekend! :D I fit 205/50-15s on 7" rims on my '67 with nothing more than a baseball bat to roll the fenders and a normal competition alignment with a little negative camber.

TT
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Postby Steve Grosekemper on Wed Oct 11, 2006 3:14 pm

ttweed wrote:
Steve Grosekemper wrote:Jeez Tom!
He wants to know what to put on the car for this weekend not what can be put on the car for with $5,000 worth of modifications!
I wasn't suggesting that he go out and buy a set of 911R wheels for the weekend! :D I fit 205/50-15s on 7" rims on my '67 with nothing more than a baseball bat to roll the fenders and a normal competition alignment with a little negative camber.

TT


Baseball bats and competition alignments still take time and money.
Just trying to give you grief and David a time sensitive option all in one fell swoop.

:wink:
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Postby David Ray on Wed Oct 11, 2006 8:34 pm

Great banter! 8) I love it! Luckily I have access to both 6" and 7" wheels and have decided to run the 6"s and 205/50x15s at all four corners (maybe I can use Tom's baseball bat later to roll the fenders).

Actually, going back in time ('67 912) is fun and yet discomforting since the last muscle/brain memory car experiences I have come from an ABS outfitted and thoroughly understood handling car (944S2), hence the weekend of performance driving in my 912. (I still haven't found out where to put the water wetter in)

I have to admit the new tires (Toyo RA-1s), lighter car and SWB experience today through some infamous back roads are making the weekend much more attractive.

Yes I know – it’s not a racer’s clinic, it’s performance driving school.
:wink:
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Postby John Straub on Thu Oct 12, 2006 1:13 pm

I use 205/50X15 on my 65 911 front and rear on 7" rims "American Mags". Works good for me. No real fender mods.
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