Hey Everyone! Here is the question of the day... I want to begin an LT1 engine build up for my third-gen and am looking for a new aftermarket LT1 block. I wanted the block to be a little beefy with thicker cyclinder walls and 4-bolt main. Does anyone know of a company that makes them? Your help is much appreciated!!!

 

There is no aftermarket block that I am aware of. F-body blocks were two bolt main (can be splayed for four) and vette's were 4 bolt. The stock blocks are strong enough to pretty much throw anything you want at them.

 

Like Shifty said, no aftermarket blocks. The stock LT1 block is good to about 8-900 hp.

 

Yes, use a GM block. They are plenty tough. Why do you think you need an aftermarket block?