I think the uncorrected hp/tq seems more realistic to me than the corrected power numbers. The dyno assigned a correction factor of 1.067 (6.7%) for the pulls, which seems optimistic. I was flabbergasted by the corrected numbers as the pulls were made. Even the best uncorrected pull (#12) yielded 358.2 hp @ 5200 rpm and 423.9 lbft torque @ 3700 rpm was very close to the usually conservative Desktop Dyno’s (DTD) 361 hp/431 lbft prediction.
The dyno weather station reported 68*F (using inside air for the session), 47.1% relative humidity, 28.86 Hg barometric pressure (steady), and 2083’ air density altitude (866’ actual above sea level). Many of the correction factors (DIN, SAE J-607, SAE J-1394, STD, etc.) use different measurements for their correction factors and when you plug in the weather data for the time of the dyno session. When plugging in the weather data into the Dyno Corrections Factors calculator from the VSeriesForums, I got correction factors from 1.019 to 1.053 adjusting the corrected horsepower for the best pull (# 12 @ 358.2 hp/423.9 lbft) from 364.90 hp/431.82 lbft to 377.05 hp/446.21 lbft. Plugging in the DTD numbers, they corrected from 367.75 hp/439.06 lbft to 380.00 hp/453.68 lbft. (BTW, I used the same factors to calculate the torque).
Using these correction factors for the DTD engine with the 2800 Summit cam of 341 hp/445 lbft, they adjusted from 347.37 hp/453.31 lbft to 358.94 hp/468.41 lbft…if the DTD numbers are to be believed. The torque seems high at 445 lbft to me, but who really knows for sure.
Anybody care to see what they get on any other calculators out there on the web?
Regardless, I’m impressed with the uncorrected numbers this motor build made and the drag strip performance (next year unfortunately) will truely tell us what the engine makes.
Dennis
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