Originally Posted by 12secSS

If it is a stock converter, you will see very little gain from locking up the TCC clutch. Stock will usually show about 5rwhp increase, unlock to locked comparison. Also, do not lock the TCC too much on a stock unit, the TCC lining GM uses is strictly designed to be soft and very unoticeable, not for holding WOT power. If you have an aftermarket converter, with a stock style TCC you really shouldn't attempt this more then once on the dyno. Only enlarged, multi disc converter can endure this abuse without an issue. You can identify these converter by the billet front cover (the part that bolts to the flexplate). With aftermarket units, you can see anywhere from 10-50rwhp gain going from unlocked to locked. The reason to do locked TCC runs on a dyno is for bragging rights, or to compare to manual dyno graphs and nothing more. Since an auto always performs unlocked at the strip, there is no need for autos to lock the TCC during dyno session. Good luck!

Originally Posted by Allgonoshow

thanx for the info guys, locked it is.
booked for 9:30 am Thursday, will post up when i'm done.
got 4 tunes to try
any guesses for #'s, truck in signature, i say 340 rwhp....