Originally Posted by Patrick G

Very strong numbers for an automatic. Are the numbers locked or unlocked?

Originally Posted by PewterZ28

Let me help you then.

Your dyno pull was made in High Ridge, MO at 10:52AM. Weather Underground reveals that it was 84.9*F at 10:54AM at the nearest weather station. You say it was 89 so let’s compromise and say 87*F

Next we need to go to http://www.crh.noaa.gov/lsx/calc.php and http://www.csgnetwork.com/vaporpressurecalc.html to get the station pressure and vapor pressure, both in in Hg.

Using 29.78 in Hg as the barometric pressure at that time and the 900' elevation of High Ridge we come up with a station pressure of 28.822 in Hg.

Using a temperature of 87 and a dew point of 71 we come up with a vapor pressure of 1.29 in Hg.

Finally, we plug in the numbers into the calculator and we get a correction factor (CF) of 1.085!

So your 377 actual horsepower is corrected to 409 rwhp SAE!!! Like I said, MM's dyno reads high but those are ridiculous numbers for a cam only A4 with the converter unlocked! CONGRATS!!!

My References:

Dyno Correction Factor Calculator
http://wahiduddin.net/calc/calc_cf.htm

This Correction Factor Calculator determines the dyno correction factor which is to be multiplied by the actual dyno data to make the resulting corrected readings independent of the effects of temperature, barometric pressure, humidity, and altitude. These calculations are derived from SAE J1349 Revision JUN90.

Air density is affected by the temperature, pressure and humidity of the air. On a hot day, or at high altitude, or on a moist day the air is less dense which means that there is less oxygen available for combustion which, in turn, means that there is also less engine horsepower and torque.

This calculator is specifically intended to help evaluate the data from a DynoJet chassis dyno run when you would like to know how the data would change if the temperature or pressures were different.

Drag racers and engine tuners... take a look at the features in the Engine Tuner's Calculator. The engine tuner's calculator now includes relative horsepower, air density, density altitude, virtual temperature, absolute pressure, vapor pressure, relative humidity and dyno correction factor!

To use this calculator just enter the temperature, absolute pressure and vapor pressure, then click on the calculate button.

Dyno Correction Calculator
Air Temperature in degrees F: 87
Absolute Pressure in inches Hg: 28.822
Vapor Pressure in inches Hg: 1.29

Dyno Correction Factor: 1.085

Copyright 1998-2004, Richard Shelquist

Additional Information:
For example, at 85 deg F, 24.71 in-Hg absolute pressure and 0.121 in-Hg vapor pressure, the engine only produces about 81.1% of the SAE rated power so that the required dyno correction factor is 1.233. Therefore, when dyno testing under these conditions, it is necessary to multiply the measured torque and horsepower values by the correction factor of 1.233 to determine the SAE corrected readings. The dyno correction factor takes into account all of the effects of temperature, altitude, atmospheric pressure and humidity to arrive at corrected horsepower and torque values.

The air temperature should ideally be the temperature of the air that is going into your engine.

The absolute pressure is the actual atmospheric pressure, also called station pressure. This is not the barometric pressure or altimeter setting as is typically reported on the local weather report.

Station pressure calculator: http://www.crh.noaa.gov/lsx/calc.php
The vapor pressure is the partial pressure of the water vapor in the air.

Vapor pressure calculator: http://www.csgnetwork.com/vaporpressurecalc.html

For these calculations, the standard reference conditions are: Air temp 77 deg F (25 deg C), 29.235 Inches- Hg (990 mb) altitude-corrected barometric pressure, 0 ft ( 0 m) altitude, 0% relative humidity.

Resources:
For in-depth technical details, see my web page on Dyno Correction Factor and Relative Horsepower and also see the page describing Air Density and Density Altitude.
A useful source for simple atmospheric theory, explanations and calculations is the USA Today Weather web site. Also, there are several weather conversion calculators available from El Paso NWS.

Copyright 1998-2004, All Rights Reserved, Richard Shelquist, Shelquist Engineering.

Richard Shelquist
Longmont, Colorado
Last Updated: May 24, 2005

Originally Posted by Tech

Eww... you locked it?

Originally Posted by Red 01SS

evil I say

Originally Posted by TruDynoSports

Got any ET's that would support those hp numbers on the Dyno Jet? Peak numbers don't really mean much, other than bragging rights. The dyno operator can also have an effect on how the overall numbers come out. I'm not trying to be a buzz kill, just wouldn't recommend you bet any money at the strip based soley on your dyno jet run. My loading Mustang dyno usually shows about 10-15% less peak than a dyno-jet. I can do ET's on our dyno and just about all of them are within a tenth of what we got at the track. I have a weather station on my dyno that corrects based on SAE J1349 Revision JUN90. I have tested a car close to your mods listed and got more like 344hp and 325tq. On the Mustang I rarely see more than 1 or 2 hp difference between consecutive runs with no changes, this is how accurate the eddy current dyno measures actual wheel hp. Like I said I'm not trying to hurt anyones feelings, just want to put 2 cent in there and see what everyone else has to say.

Aaron-

Originally Posted by ragingWS6

First run, the converter unlocked on me. The others it stayed locked.

Originally Posted by Tech

What does this mean? I'm confused but don't worry... that happens alot.

Originally Posted by ragingWS6

You are in for a BIG surprise by next spring my friend...a HUGE surprise.