What kind of power gains are possible?

[kerrige]

I have a 2000 Z-71 5.3, I have cold air, elec fan, nelson tune. Im in the process of adding Texas Speed Stage 2 heads, 80mil Throttle body, 45lbs injectors, 224 cam, Long tubes, Fully built trans with a 2500 stall. I already have 4.10 gears and a tru-track. What kind of power should I get from all this? I know Ill need a retune. Has any1 done something similar to this? Is 400 WHP possible? And also What am I missing? any sugestions?

So you decided to ditch the trinity and shorties? Wow that's a pretty strong about face on the whole thing, but anyways.....
I would go bigger on the stall. 3200 should be good. I wouldn't waste time on the 80mm throttle body though. I would go with a toss/Nnbs intake with 87/90mm tb if you plan to upgrade in that area. As for power to the wheels I would expect in the neighborhood of 350hp with those mods. Maybe a little more. This combo is one of the most repeated in the truck scene, t there is a reason for that, it's because it works and people end up very happy with what they get.