<VV> an almost stupid question:

[Wade Halsey]

-------- Original Message --------Ray Rodriguez wrote:
> What is the correct tire size for my 65 Corsa coupe?  By correct I mean the size that would cause my speedometer to read correctly =P.  
> I am looking at a tire height chart to see how far my new wheel/tire combo will throw off my speedometer and I need a point of reference.

Hi Ray: Earlier this year I had a set of 195-75-14 tires on the front of my 69 Monza. This 
resulted in rubbing in turns if I had much weight in the car. I rounded up some mounted tires 
and ran tests on a local highway with mile markers and kept careful records. Below are my 
findings. I realize the rated revolutions by the manufactures don't agree with my findings but I 
ran the tests a second time to get accurate numbers and this is what these particular tires 
recorded on the left front (odometer reading) of my car. I bought a new set of 185-75-14 
Pirellis from Tire Rack and my tire rubbing is gone. Your 65 came originally with 6.50 x 13 
tires instead of the 7.00 X 13 on other LM's so the 185-75-14 diameter of 24.9" should be a near 
ideal replacement. (Assuming you have 14" wheels, of course)

Wade Halsey

Accuracy of tire sizes over measured 10 miles.

Tire Size  Odometer       PerCent     Tire      Rated
            Reading        Error       Diameter  Revolutions
            after 10 miles                       Per Mile


Original Spare-No measurable odometer error
7.00 x 13    10          0%         25.5",    825 RPM

195-75-14;   9.80;       2%   slow  25.6",    812 RPM

185-75-14;  10.15        1.5% fast  24.9",    835

185-70-14;  10.4;        4%   fast  24.3",    870

185-80-13,  10.4;        4%   fast  24.6",    848 RPM.