They just finished my build and they are tweaking the tune . We went ahead and installed the Livernois stage3 heads CNC Ported Stage 3 GM LS-Series Cylinder Heads

GM 243 casting
5 axis CNC machined
Fully assembled
220cc Intake Runner
Intake Flow Rate 310 CFM
Exhaust Flow Rate 245 CFM
Stainless 2.020 Intake Valves
Stainless 1.575 Exhaust Valves
GM valve seals
Super 7 locks
Livernois dual coil valve springs good to ~ .690 lift
Livernois titanium retainers

Also to compliment the HEADS we went with the Speed Inc. SC3 Blower Cam. SC3 226 234 .598 .599 117
My builder discussed this with speed inc and they decided to go for the most power as i did not mind a little lope at idle.

All i can say is the power that has been made is incredible . I was pleasently shocked . I have only ever driven a couple of vehicles that pull this hard ....one of those vehicles is a 2006 Dodge viper and the other a callaway corvette with the eaton blower package .

My tuner is having troubles with getting the Trailblazer SS AWD to not studder when the gas pedal is nailed off of idle . There is a studder that feels similar to loosing a couple of spark plug wires for 1 or 2 seconds . When you are cruising at 50 mph in 3rd or OD and you are on level ground ..RPM's are about 2700 and if you nail the gas pedal quick it will do this studder/bogg something similar sounding to my old GTO 1970 when the timing was not dead on and you would nail it ...it would do a couple of quick backfires amnd no power for about 2 seconds then it would go like a bat out of hell.

I hope he is able to figure this out without taking timing out of the tune and loosing power . he has been working on this for about a week and he has tried a ton of different things in the tune and no changes at all.

One thing I would definitely recommend no matter what you do is get forged pistons and rods . Our stock rods,bearings ,pistons etc do not like the boost or the igher comp ratio. My builder dropped my CR down to 9.8:1 and alot of the guy's on the other forum said there is no way my tbss is going to make power at that low of compression . The maggie i am running is the MP112 not the MP112HH. I was told by a bunch of guy's that the blower is way to small to fill heads,cam and cylinders with enough boost to get it over 3 or 4 lbs without spinning the blower so fast that it will heatsoak so bad it will still not make more boost and it will run like ****. Well she is pushing 8-8.5psi and it is running so strong. I just hope that they can get that studder out of the tune and it will be perfect .