Correct '71 M21 speedo gear?
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Racer
Joined: Feb 2009
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Correct '71 M21 speedo gear?
What driven speedo gear should be in a '71 w/ M21 and 3:36 ratio diffy?
Have a brown one w/ 18 teeth that I "think" is for the original calibration.225/70/15 Goodyear Eagles came off it. I changed to 255/50/17 tires. The online calclators say that should be 1.3% difference- not enough to bother changing from a stock speedo gear I'm thinking- assuming the old Eagles were the original size to start w/. Thanks.
Have a brown one w/ 18 teeth that I "think" is for the original calibration.225/70/15 Goodyear Eagles came off it. I changed to 255/50/17 tires. The online calclators say that should be 1.3% difference- not enough to bother changing from a stock speedo gear I'm thinking- assuming the old Eagles were the original size to start w/. Thanks.
Last edited by kunkle; Jul 12, 2009 at 05:28 PM.
Le Mans Master
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