Mopar Action On-line – Tech Questions


Tech Question

Mike Follis, Bevidere, IL, 1966 Plymouth Belvedere II 383

I am rebuilding a Plymouth Belvidere II, putting in a 383not sure if I will install 727 Auto. or 4-Speed, The car was originaly a 225six with 904 Trans.

I would like to install a posi trac. rear end, maybe a Dana 60, the problemis I am not sure what is the best way to go, I have redone the front end,bushings, struts & bigger torsion bars.

Hope you will share your experience and give me some Ideas on a good rearend, and if I have to swap out housing or use the one I have now forupgrade.

Mike: I’m curious as to why you changed the struts? The only way I’ve everseen ’em go “bad” is by being bent by tow hooks!

OK, anyway, if you’re gonna be a Mopar guy, you’ll need to wash that Chebbyterminology out of your mouth and brain. Repeat after me: “Sure Gripdifferential. Sure Grip diff….”.

The Dana 60 is a Salisbury-type differential, i.e., no drop-out sentercarrier section. The casting is permanently welded to the axle tubes. So, ifthat’s what you’ve gotta have, it’ll require a complete new axle assembly.But your current 8.75″ is plenty strong enough for anything a 383 can throwat it. The axles are super strong, the tapered roller wheel bearings are asgood as it gets, etc. Just pick up a Sure Grip-equipped center section, inany ratio you want, and pop it in, adjust the wheel bearing endplay (shootfor 0.005″) and you’re good to go. Try to get one with a casting number thatends in 742 or 489, those were the strongest.



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