LA360 compression
I’m kinda on the engine builders side here. I wouldn’t put that thing together if a customer came to me with the OPs goals. I would advise him to go back to the seller he bought it from and ask for his money back. The engine builder is giving him good advice FOR HIS GOAL of 400-450 hp. The only result of screwing that thing together the way it is and making 275-300 hp is an unhappy customer.