Think again - the dyno measures power and torque at the rear wheels - nowhere else. It doesn't give a damn about whats driving the wheels.

Tommy

 

I did include this in the post:

The gear needs to be a factor as it changes the way torque is applied.

 

For the record, i read in the 911 & porsche world magazine that the ac compressor takes anything from 20-35Bhp.

And Chris White is right, the ac compressor doe not turn off at WOT

 

"Then why, in normally aspirated cars, they use the gear that is closest to 1:1?"

Less drive train/static loss.

 

"Regardless, Todd, you need new dyno operaor..."

So you are thinking the low numbers were mostly operator erors and not maybe way off tuning? That would certainly make me feel less worried

 

Only one way to find out. Try a more experienced dyno operator that can map boost and AFR. Have them output a chart that has the HP and TQ on the Y-axis with the RPMs on the X-axis. Also, be sure to use 4th gear only.

I don't buy the "greater drivetrain loss" in different gears. Hogwash.

 

Daniel,
I think you are getting confused by the fact that the dyno shows a torque curve that looks like crank torque.
In fact, in 4:th gear, rear wheel torque (which is actually what is measured here) should be approximately 4 times higher than crank torque (due to the final gear ratio which is around 4:1).
The displayed torque curve is actually calculated and corresponds to something like crank torque reduced by drivetrain losses.

Now, how would you define rear wheel HP then if HP=TQxRPM is not true ??

Tommy