I'd be really happy if it all held together at 10 pounds. At 6 it's already a handful! I wish somebody else would build a similar combo so we can compare notes. I think these Ebay GT45s are a unique beast. I've been tempted to try a different turbo but this one spools fast and makes gobs of power with my combo. I'm thinking im close to 500hp now at 6psi and 550 would be easy.