[Markj2222]

Alot of magic happens with VVT on our engines, disabling it will result in less power and economy.

Valve lift doesnt help much, its easier to turn up the boost then to make new cams.
Getting aftermarket pistons allows for a more aggressive scavenging cycle (aka faster turbo spool)

VVT can give you greater cylinder pressures at low rpms, or greater turbo spool depending on load.
High rpm it can once again give you higher and longer cylinder pressures, or give you quick spool depending on load.

Any tune will be extending the cam profiles to give you more of what you want when you want it. +45 lb-ft of torque and more boost with an aggressive cam tune. Slightly better economy when off the boost as well. +6 MPG overall, in my experience.

 

[Markj2222]

Heads already have over-sized runners. If you want to push these things turn up the boost!

 

[Markj2222]

The tuning is the least of my issues to be perfectly honest. I have a personal GM tuner that helped write their coding and still help them with patents and will occasionally help GM engineers out. So tuning is the least of my worries. I just really need the hardware.

Well i got the hardware and a tight build, sooo many tunes, and my biggest issue is accurately fueling over 22 psi.
8 bit MAP and Charge tube readings. With a pwm MAF sensor in play it will fuel correctly under load, but once i start shifting gears the ECU sh***s itself.

Still waiting on a clever tune, but trifecta gave me a tune that never worked after a day at the dyno.

Idealy to really push these things we would need a full aftermarket ECU