Dyno help needed.
Thread Starter
Launching!
Joined: Mar 2002
Posts: 244
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From: Houston, Tx
Dyno help needed. I dyno'd the car about 6 months ago and pulled 333rwhp 349rwt. Last week I installed dynatech lt's, deleted cats, custom x pipe/bullets. The run 6 months ago was 82.6 degrees F and had a correction factor of 1.00 (aka perfect). Today I dynoed and pulled 328rwhp and 345rwt. However, todays pull the intake temp was 50.3 degrees F and I had a .93 correction factor. The actual max hp and torque was 354/371. Could 30 degrees ACTUALLY cause a 7% increase in power?
I'm HOPING that the 7% is a bit much. I understand that cooler air is more dense and therefore gives more power. But I just can't figure out how I could have lost 3 corrected horsepower. I gained an actual 21hp and 22ft/lbs. Do you think this is only because of the temperature drop?
I'm going to autotap the car and check my knock retard for false knock due to louder exhaust and vibration, and check the O2 for possible leaks in the collector. If these check out ok, I'll have to go back and dyno when conditions are more favorable to a perfect correction factor to see if there's any change.
Any tips, comments, or suggestions are MUCH welcomed.
<small>[ February 08, 2003, 02:44 PM: Message edited by: Turk01SS ]</small>
I'm HOPING that the 7% is a bit much. I understand that cooler air is more dense and therefore gives more power. But I just can't figure out how I could have lost 3 corrected horsepower. I gained an actual 21hp and 22ft/lbs. Do you think this is only because of the temperature drop?
I'm going to autotap the car and check my knock retard for false knock due to louder exhaust and vibration, and check the O2 for possible leaks in the collector. If these check out ok, I'll have to go back and dyno when conditions are more favorable to a perfect correction factor to see if there's any change.
Any tips, comments, or suggestions are MUCH welcomed.
<small>[ February 08, 2003, 02:44 PM: Message edited by: Turk01SS ]</small>
Re: Dyno help needed. This is not a direct answer but if on a 90 degree day I run a 12.25 @ 111.5 on a 50 degree day I will run an 11.95 @ 113.5. So yes temp is a major factor in making HP and to a lesser degree the barometric pressure and dew point. These environmental conditions are used in calculations to come up with the density altitude.
John
John
