Twice I have dynoed my car on the same AWD Dynojet. Once when it was 50 degrees F and again recently at 90 degrees. Both at 5280 elev. Does the SAE correction for T, P and humidity (1.22 in the first case and 1.27 in the other) make the hp and tq numbers from the two days comparable? What sort of % error should one expect between different days and dramatically different atmospheric conditions? Even with the correction, would the turbo spool be different (laggier) at 90 degrees than at 50 degrees?

Just trying to figure out if the 6-8 ft lb drop and slightly slower spool is due to atmospherics or the underdrive pulley I replaced with stock recently (tired of p0340 CELs).

Superg

thanks

Superg

if you're trying to compare both runs, (50 vs 90) and the difference in power between the two, overlay both run files on the same graph and post it up. Making sure that the CF setting is at UNCORRECTED....this would show real WHP on the 50 degree day and the 90 degree day....there should be a difference.

With the CF on SAE, it adjusts both runs to as if there were run @ say 70 degrees....that is why one got multiplied 1.22 and the other 1.27.

If you had an underdrive (or lightweight) pulley on for the earlier
runs, and went back to stock for the other, that probably
IS why you lost 6-8 ft lbs.
If you kept getting CEL with the underdrive pulley...just go
with a stock diameter lightweight one.
You'll get 80-85% of the power gains, but without any of the underdrive
pulley drawbacks...and therefore probably no CEL's.
LW Crank pulleys are a cheap ($125) way to get more power to the wheels.