The 4.10 gears just happened to be ideal for people running 1.88:1 2nd. gear Muncie 4-speed transmissions on 1/4 mile dirt tracks back in the late 1970's. The Chevy 3/4 ton rear end with the full-floating hubs was a favorite with those of us who ran roundy-round cars. Running 2nd. gear against a 4.10 rear end gave us a 7.70:1 final drive ratio. That was just right for coming off the turns at 3500-4000 RPM, and hitting 6,000 by the end of the straightaway. We snapped up every 3/4 ton 4.10 gearset we could find, along with the special-offset carrier that it needed to fit the pinion gear right. Then the axle gears and spider gears got welded together for a locked rear end, and we went racing! Lots of gearsets got trashed that way.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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