A few of my competitors on the dirt tracks ran Muncie 4 speeds behind beaned-up 350's with few, if any problems. Hammering on and off the throttle at 3-6K RPM several times a lap with the transmission in 2nd. gear had a habit of showing up weak spots pretty quickly. The aluminum case Muncie transmissions would handle 2nd. gear that way, but if somebody tried to use 3rd. with a lower geared rear end, the case would split wide open after a few laps. The Saginaw has a cast iron case, and appears to be much heavier and more durable than the Muncie. That's a misconception - - - -apparently the gears and synchronizers are a little weak.
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
Love your enemies and drive 'em nuts!