That's why I asked if it's a flywheel or flexplate. If a flexplate, perhaps he's putting it on inside out/backwards?

 

Tried using the flexplate for that motor, But it was a different size, Unless they sold me the wrong part, Nah couldn't happen, My dad thinks it might have too much torque for a Camaro flexplate, I don't know, Thanks for everyone's input

 

so are you using a flexplate or a flywheel. I'm kinda lost through all the posts

 

Too much torque from a 305? Doubtful. Im still running a stock flex plate on a very well worked 350 and never had an issue. Where is it cracking? Have you actually checked the starter for proper tooth alignment? If I dont shim my starter it causes all sorts of issues......

 

My bad, I'm using a flexplate, On a automatic tranny, And it keeps busting where it bolts to crankshaft, If I get it out tomorrow will post pictures

 

My only other thought is a bent crankshaft

 

A bent crank would cause serious vibrations. You would know if you had a bent crank. I know Im beating a dead horse here, but its either being installed wrong or its the wrong part. Im at a loss as to what else could be causing this.....

 

I will try a different supplier, Maybe they gave me the wrong part, I tried 1 and went to a camaro salvage yard

 

oh, so now its a flexplate? thats easy. its the wrong part. there is a difference in the flexplates between those years. its slight, but i believe the indent where the bolts go to the crank is deeper, thus forcing the torque converter against the trans input shaft. since the flex plate is a lot weaker than the trans and torque converter, that will break first

 

That kinda makes sence, How do I figure out which flexplate I need