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Re: Off-diameter tires

On  6 Dec 95 at 21:49, Brooks Ellis wrote:

> I'll just go ahead and stick 205 vr (sr zr whatever) 50 15 boys on them 
> wheels. 
>     Would this 'screw things up BADD'? Could I get my spedometer 
> recalibrated for the smaller tires for a low cost? would it $#%^ up my 
> ABS/whatever else uses tire size to function?
One of the tire companies (I forgot which one) has a web site (I 
think it's Goodyear) that'll help you figure out what different tire 
sizes will fit on a given size rim (15 X 6 in your example), and 
tells you the overall diameter of the tire.  This info would probably 
help you out a lot.  I don't know what diameter you're shooting for, 
but on 6" wide rims you could probably fit 215, or maybe even 
225/50R15 tires, which would give you a larger tire contact patch, 
and a larger overall diameter that I suspect would be closer to what 
you have now.  When you change the tire diameter (outer diameter, not 
inside diameter) it not only changes the speedometer calibration, it 
also changes the RPM range your engine works in.  A car that turns 
2000 RPM at 60 MPH might spin at 3000 RPM at 60 MPH with a smaller 
diameter tire.  I don't know what's involved in recalibrating an 
Audi speedometer, though.

Hopefully, someone else can get you the URL for the Web site I 


   '85 Audi 5ks
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