a833od behind 383

The 833 OD is strong enough for a stock 383, especially if you aren't planning on racing it. There's a few members over on Cuda-Challenger that have run 833 OD's behind 440's that have been to the track numerous times without breaking the transmission. And that's in a heavier car.

A cast iron case would be the way to go though, as it eliminates one of the weakest parts of the 833 OD. Still, even an aluminum cased OD should live just fine behind a stock 383 that doesn't see much track time. It may not last as long as an iron cased 833 because the shaft bearings will eventually get sloppy in the case, but on the street that shouldn't be something that happens overnight.