You will be very glad you stayed with turbo in the long tun. When you start it doesn't seem worth it for the HP... Now I went to the dyno at 8 psi and dynoed 525 RWHP and 600 RWTQ. Just for the hell of it I turned it up to 12 psi and made 581 RWHP and 700 RWTQ. My turbo is choked and peak RPM was at like 5000 ish. Show me a N/A engine that idles at 800 RPM with 14" vac and make that kind of HP and torque. There is lots left with a larger turbo as well. I ran close to mid 11s in a 4200 lb brick so far I can't see any down side of a turbo except the added complexity. Oh and the truck has never seen a drop of fuel over 91 octane on those tunes.