Originally Posted by BlewSilverado

I realize boost is just a measure of resistance. The interesting thing to me is the 3 different results on bone stock trucks ranging from 6lbs (from a pm I received not the 5.3 with a ls9 cam) one with 8lbs and the last with 9.5. The only other variable I could think of is altitude or maybe different heads from the different year models? When you get into mods such as airbox, headers, cam, TB, then of course that changes everything.

This is my third supercharged LS vehicle so I have a little experience with mods and the effect of mods on a supercharged vehicle. I am trying to predict a base line of what to expect. If I put the tvs on and end up with 6lbs I probably wont be happy but on the flip side if I throw a 10% od balancer on and am at 12lbs or more I have probably pushed the envelope too far.

Thanks for all that have given your results and input.

Originally Posted by Ford_Assassin

I have a Roush TVS 1900 on my 4.8, which until recently I thought was a 5.3, until I hooked up a boost gauge and its making 11 psi at WOT/6300 RPM. I put a scope down a spark plug hole and guess what? I have a 4.8 (flat top pistons in a 2001 = 4.8).

Still made 430/440 HP/TQ to the wheels in 100 degree heat.