Help me guys, I have a '75 vintage 350 4-bolt main block that I'm considering building someday for my RS. I seem to remember a conversion kit to change the 2-piece rear main seal to a 1-piece. Am I nuts? OK, more to the point, does this exist? If so, do the crankshafts interchange? Oh, yeah - is it expensive? Thanks. :hail:

 

I've seen kits that allow you to use a 2 piece crank in a 1 piece block.
I think it might be hard to do it since the 1 piece crank is bigger at the seal or something.

Ron

 

Yes I just ordered and returned it from summit, I was told I'd need it, then ended up using a diff. block, then Im not even using that one now... but anyway

Yes, its like $100-$150 I forget exactly how much it was but I know it was expensive for a single peice of alluminum.

 

OK, that helps. Not sure what I'm going to do yet, the motor that's in the car is in great condition. I guess I've got time to weigh my options. Thanks.