pwr-346

Hey everyone,

Just got my car back from the tuner, with some unexpected results. And i was wondering if anyone has had similar outcomes.
Car is a 2004 Holden Commodore with a LS1 and 4l60e.
I got the auto built with a 3000 stall, and is running 3.7 gears.

The engine has got valve springs, 1 3/4in long tubes, to hi flow cats and twin 3in exhaust, with a mafless tune made 315rwhp N/A. I added the D1SC, along with a switch to e85.

Tuner got the D1 to 10psi at 5500rpm using a 3.7 pulley, which made 501rwhp and 730ft lb torque. Im not complaining just want some insight to how this came about.

Question 1 - Isnt that torque high and early for a procharger setup, im assuming that the 3000 stall along with the 3.7 pulley is allowing decent boost in early enough to create that torque.

Question 2 - the tuner also said it started falling over after 5600rpm, where most readings ive seen keep carrying the power further up. So could it be the cam is running out of puff, or belt slip, or somethig else.

Any feedback would help.

Thanks

(dont worry about the rpms on the read out, the correct gear ratio wasnt in the tune during the power run)

ken6881

Something is wrong with the dyno sheet because the hp and torque when plotted on the same scale should cross at 5250 EVERY TIME. these obviously do not when the car made 680ft lb of torque at 5060 rpm it would make 655hp and the graph shows 500ish its is a mathematical formula so something is up with the way he is calculating hp.

Blown06

iTrader: (32)

I see a jacked dyno print out and possibly some belt slip.

I'm not sure which is which. I'll assume the top line is supposed to be torque. Prochargers don't make flat torque like that. It's more proportional with rpm like an n/a graph, because with a centri.......as rpm goes up so does boost. They don't make a lot of boost early on.

That thing isn't making 680+ rwtq below 2800 rpm.

pwr-346

Thanks guys. Never knew about the 5252rpm crossover. Now to make a decision on how to move forward with this.