I also want to hit 400's this late spring or summer. I think my block and heads are ready for it. Forged bottom end with refreshed heads, 3 angle valve job and GSC springs and retainers. I only need the fuel system figured out and what turbo I want to run. The Blouch Dom seems to be extremely popular with us, but is there anything else out there that is comparable? One thing though: Can I hit the 400's with a stock location turbo AND a larger top mount?