Is there something in the PCM that limits power when the brake is on or when you are not moving? I try and power brake and I have no power. It will not try and build rpms or even strain the brakes. As soon as I start rolling I have a rush of power??

 

I am not sure why you are having a problem. My truck will stall up to about 2500 rpm and yours should as well. If I hold it at part throttle opening I have seen over 4 psi of boost before launching at 2500 rpm. I would ask Allen if he can help you out with this. If it is in the tune I am sure he will be able to help you out. I think that something is wrong with your tune or throttle linkage and I hope someone can help you out with it.
Good luck

 

i think it probably is in your tune, mine did the same thing and allen worked with me to correct it, but since ive got the intercooler my truck really came to life and will roast the tires into oblivion at 6#s of boost, you need to get some values for him to help dial in your tune- L-trims at steady speed, I.A.T.s and timing at W.O.T . ,Knock Retard at W.o.t. and O2s should be around 920mv. im sorry to post if you already know this, just some thoughts on your prob, good luck!

 

Mine does the same thing. It just bogs down and wont build rpm's.

 

I read somewhere (on this site) that GM was working on programming to do exactly what your describing. As you build rpm but don't register tire spin (brake stalling) the PCM pulls timing. I would think it can be tuned out but I was under the impression it wasn't in the PCM's yet. I thought it was coming in 06+ but maybe they snuck it in early.

 

I don't see a stall in your sig. Without one it will not build any boost because the stock converter will not let the motor rev high enough.

 

The electronic throttle control(ETC) vehicles have "Brake Torque Management"(BTM) which will limit throttle opening if your foot is on the brake. This can be disabled in the tune.

 

so does that mean I cant power brake too? does that also mean I cant do a burnout?

 

There are also several other "Torque Management" and "Abuse Management" parameters in the factory calibration that limit power output under various conditions. WOT launches would be one of those conditions.

 

Mine is still stock no tune only mod is exhaust. I've never had a problem. What I do is apply brake softly apply gas as the back tires have forward momentum apply alot more pressure the the brakes and you'll be smoking'em too.