I'm curious, is it possible to use an older two-piece rear main seal 350 in place of my current block?? Will the knock sensor and stuff like that all swap over to the older style block??

I ask because I am basically lacking only a crankshaft to build a 383.. I was planning on building the 383 with the older 2 piece block because it is

1. 4 bolt main
2. high nickel & lead casting.
3. Who wouldn't like to see a stroker TBI

 

Yes, it will work. You will need a different flexplate, but you'd need that unless you got an internally balanced stroker crank, anyway.

For the record, the knock sensor goes in a coolant jacket drain hole that has been in SBC's since 1955.

As to your points:

1. 4-bolt main blocks are actually a little weaker than 2-bolt main blocks in the web where the outer bolt holes are.

2. Later 1-piece rear main seal blocks are generally of better quality than the earlier blocks, especially those cast and machined in the 70's.

3. Sure, but that doesn't mean it has to be a 2-piece RMS block.

 

Thanks for clearing that up for me.

The only reason I would use the older block to begin with is it's all I have. The only 1 Piece RMS I have is in my truck and gettting me around from day to day