Just got my 383 together it has 13.3 compression, Afr 210 cnc heads, comp cam 12-906-9 cam 276/284 @ .050 .630 lift 17/8 headsers/3"flows powerglide in a all steel 68. Anyway I tool it down the street after a few miles I got on it. Wow when I shifted into high gear the driveshaft broke right in the center, when that happened it took out my freshly put together powerglide case. What would you guys recommend on a shaft? stock is not working. I think the motor is close to 600 HP Thanks Dan

Been there and done that, fun ride huh? Makes a lot of noise. You might also want to check your rear end out especially the pinion, seal, bushing. Mine also broke my tranny case and destroyed the exhaust.

I had the driveshaft for my car made at a local drive shaft shop. It is supposed to be "un- breakable" it was not very expensive. If I remember right (without digging through receipts) it cost ~$200-250.

If you don't have a local shop that can build and balance a heavy duty driveshaft you might want to check with Denny's Driveline/Driveshafts.

Make sure your rear u-joint it secure and in the locators ir no matter what driveshaft you put in will get bound up and broken.

I had the same grief years ago. I traced the cause to a rear u-joint that wasn't installed correctly. It took out the rear yoke, driveshaft, th400, converter, and the flexplate even sawed into the rear of the block. It's enough to make you real nervous when you take it out after you get it back together again.

the rear end and drive shaft wasd the same as last summer, but I have at least 100 hp more now. Yes it scared the hell out of me real fast. It also got into my exhaust.What diameter is your new driveshaft is it made out of chrome moly steel/ Thanks Dan

My drive shaft is steel (seamless), I am not sure on the diameter (never actually measured it). I can tell you it is quite a bit larger diameter than a stock one, and the steel is a thicker gauge. I have 3" exhaust on my car and the driveshaft is quite a bit larger than that. Sorry for the lack of specifics, if you really need to know I will climb under the car with a pair of calipers and measure the diameter.