Tire Diameter

These links have what you need: http://www.panteraplace.com/page18.htm http://www.panteraplace.com/page121.htm

[This message has been edited by Mike Dailey (edited 03-18-2003).]

According to the information in the book "Pantera, the ultimate portfolio", pages 16 and 19; if you are talking ORIGINAL size (1971) they are: Dunlap, Michelin, or Goodyear radials, Front- 185/70-VR15, Rear- 215/70-VR15. You'll have to look up the diameters yourself. Marlin.

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Originally posted by MARLIN JACK:
According to the information in the book "Pantera, the ultimate portfolio", pages 16 and 19; if you are talking ORIGINAL size (1971) they are: Dunlap, Michelin, or Goodyear radials, Front- 185/70-VR15, Rear- 215/70-VR15. You'll have to look up the diameters yourself. Marlin.

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The formula for tire diameter is as follows- Example (215/70-VR15) 215 is width in millimeters. divide that by 25.4 inches and you get tire width (8.46 inches) Take the tire width 8.46 times the aspect ratio (70) and you come up with the tire section or 5.93 inches. Add up tire section times 2 plus the rim size and you have the total diameter 5.93+5.93+15.00=26.86 tire dia. This works for any tire and rim combination.

Judy & I ran many T & D rallies in the old days, and had quite a few conversations with radar police. 26-1/2" dia. tires allow the speedometer to be awfully close to perfect with a stock ZF. If this isn't a major concern, and your Pantera engine is healthy, a bigger diameter tire will simply raise your gear ratio slightly, increasing fuel mileage and top speed a little at the same rpms you now use. Just be careful in front to not go too big or you'll have massive, expensive interference with sheet metal. The rears are normally OK for clearance with all but tractor-sized tires.

Throw out the calculator. Plug your numbers in here:
http://www.discounttire.com/dtc/brochure/info/tireMath.jsp