Tires

My '72 911 has 195/60R15 tires on 6J15 Fuchs in the front, and 205/60R15 on 7J15's in the rear. The car also appears to have been lowered in the rear. It now sits back on its haunches rather than having a downward appearance. There are signs that the tires are rubbed occasionally but not enough to blister the paint on the rear fenders. I think most of the marks on the rear tires are probably from scraping curbs.

I'm going to try to adjust the rear ride height using the info I've found in Bruce Anderson's book and Haynes. But I'm not sure whether I should stick with this tire combination. I have seen pictures of other
72-73 911s with 6's in the front and 7's in the rear. Any ideas what tires these cars might be running?

Is it possible to adjust the spedometer to take into account the circumference differences?

Thanks

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Greg
72 911S

[This message has been edited by ggalloway (edited 08-02-2000).]

Greg,

I have 205/60x15 tires on all 4 corners of my '77 911. They are mounted on Fuchs 7x15 wheels. I had to roll the front fender lips for wheel clearance, but the rear wheel/tire clearance is OK.

As far as height is concerned, the rule of thumb is 25.5 inches from garage floor to the lip of the center of the front wheel well and 25 inches to the lip of the center of the rear wheel well. You will find some 911's (e.g. track cars) that are lower, but you may have to make adjustments to the suspension and steering racks (i.e. bump steer) as you go lower. My '84 Carrera is 24.5 inches in front and 24 inches in rear and my only problem is steep driveways (ouch!).

Adjusting your rear ride height is not a simple task, since you will probably need to re-index your torsion bar covers. See the tech article on Pelican Parts web site about replacing torsion bars and height adjustment.

Your speedo can be re-calibrated for various tire/wheel combinations. Try North Hollywood Speedometer or Palo Alto Speedometer; I believe both have web sites.

BR

Palo Alto Speedo is at http://www.paspeedo.com/

I called them about calibrating my speedo IN PERSON, meaning taking the speedo out, making the adjustment and putting it back in. They said it would be in the range of $250 +tax.