My core engine is a 4.00'' bore 89' truck engine, 2 bolt main cap.
If I used an APR main stud kit what is the most hp. or torquue I could put through the block before I damage it.
I was looking at making a 383 nitrous oxide engine but with the 2 bolt I don't think I can put more than 650 hp through it.
What do you think?

 

stock for stock, a 4 bolt isnt much stronger, the extra bolts keep the caps from "walking" ---- prematurly scaring the bearings.

if you have 500 dones, splay the 2 bolt, it wont ever spit a crank out then.