Ok guys i need your help, i just realized i might of screwed something up. I have a 350 block casting # 10066036 and it says that it has a 2 piece rear seal. Well......last week i ordered an aftermarket 400 crank (for a 383 setup) and for some reason i got a 1 piece seal!! Will that 1 piece work instead of a 2 piece?? I just noticed it tonight, i looked at the end of the crankshafts and the ends were different. What should i do?!?!?!

 

You gotta send it back and get one for a 2 pc rear main seal block.

If you would have done it visa-versa, then you "could" make it work. But you didn't, so you can't.

Of course your other option is to get a 1 pc rear main seal block.

 

Call the company you got it from and get them to swap it out. You CANNOT fit a 1 piece rear seal crank in a 2 piece rear seal block. It won't happen. If you had the opposite problem, a 2 piece crank and a 1 piece block, you could use an adapter to make it work.

But alas, you just need to get them to get you the right crank. Call and see if they will work w/ you. A good company should.