The motor is a stock LQ4 with a LS1 intake and a sloppy best cam 219/225 110Lsa and .595 lift and a cast 7875 turbo. It feels great in the mid range (3-5k) but feels like it falls off in the upper rpm’s. I’m assuming the LS1 intake causing it. Heads I’ve got on hand are 706,799,823 heads. The 706 heads with a substantial bump in compression would help across the board but not sure if the intake would still choke it down. Or mill the 823 heads a little and get an LS3 intake? Looking for any advice or game plan

 

bigger turbo

 

MSD intake if it's still made for the LS3 heads.

 

This is the way.

 

If you want the most lack luster results ever for the most money spent, chase things like expensive intakes. Heads are always nice, but I doubt thats a bottle neck. Might start with something useful like how much boost you are running. Tune up, fuel used, etc...

Its not the intake or the cam. It should pull to 6600++ with a turbo. You’ve got other issues if it doesn’t. What is the boost at? Just add a progressive boost curve if the turbos not maxed out.