4-speed gearing

[72cj351]

I have a 72 mach1 w/a 4-speed, the rear end gear is 3:25, rpm drop between gears is fine but 1st gear seems very high, is it possible to change just the 1st gear ratio on a top loader. Thanks for any help.

 

[MeZapU]

Not without changing the counter shaft and all of the rest of the gears to make it a close ratio transmission.

 

[c9zx]

As with many things, it can be done but it requires replacing so many parts that it is not worth it. If you really want a close ratio 1st gear top loader you'd be better off buying one and selling the wide ratio top loader. Based on your other post that it turns 3000 at 65 MPH and has a 3.00 gear, I'd confirm the Gear ratio and speedometer accuracy before proceeding. I calculate just under 2700 with a 26 inch diameter tire, 65 MPH, and 3.00 gear. Top loader sources, David Kee, Dan Williams, and Top Loader Heaven. Chuck