Originally Posted by GMRULZ
Frank or Brent,
I think the 20% loss is due to 3 things, 1. 20 inch wheels, 6L80E trans that is one beefy mother and the GM computer is very conservative and loves to pull timing, I ran 2 runs back to back stock and put down 319rwhp on my L99 then pulled the ECM fuses to clear the LTRIM`s for about 5 minutes, immediatly ran it again and gained 8rwhp, no cooldown.
American Racing is seeing 30-50rwhp w/ their header and x-pipe kits tuned. That L99 exhaust setup is pitiful...If you did the exhaust on that car and still have it laying around take a look at it.
I`m thinking a Whipple for mine, you can`t spin the L99 in the high rpm`s because of the lifters, so lets make power down low w/ a screw style, and at least on the mustangs isn`t the whipple the most effecient at the same boost levels? Now if I had a manual LS3 w/ the 6600 redline a Procharger would be my choice for certain.
I bet that car is a whole nother animal now! Picking up 158rwhp is freakin sweet
Hey Mike, I'm right with you on the drivetrain loss. The trans loss is kind of crazy though. The SRT (NAG1) trans will hold 550rwhp stock and it has no wheres near the loss %. The Whipple is great, just nothing was available from them, Magnuson, KB, etc. when the customer was ready to go. This job got initiated at the end of June and PC was the only company giving out shipping dates at that point. The power actually comes on really nice, the gains were great even down low. We may turn up the boost a little in the future to get more out of it. This car was tuned on Tuesday (unfortunately the air temps were up around 100 deg).
We'll post again once we up the boost and retune, hopefully on a cooler day.