if car is tuned in cool weather, will it run rich at the track in warm weather?
07-16-2002, 03:33 PM
#1
if car is tuned in cool weather, will it run rich at the track in warm weather? does the PCM calibrate for heat and humidity?
i got my car tuned on a dyno with wideband and LS1edit in nice cool weather.
but now it is hot as heck when i drag race, and i wonder if the car is running richer now becuase the PCM won't lean out the air/fuel mixture enough to give me maximum power.
i know in cold weather, you want more fuel in the mixture. in hot weather, less fuel makes more power because the air is less dense. does my PCM do this? or do i need a MAFT to maximize the car's potential in the summer?
thanx!!
i got my car tuned on a dyno with wideband and LS1edit in nice cool weather.
but now it is hot as heck when i drag race, and i wonder if the car is running richer now becuase the PCM won't lean out the air/fuel mixture enough to give me maximum power.
i know in cold weather, you want more fuel in the mixture. in hot weather, less fuel makes more power because the air is less dense. does my PCM do this? or do i need a MAFT to maximize the car's potential in the summer?
thanx!!
07-16-2002, 04:25 PM
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Re: if car is tuned in cool weather, will it run rich at the track in warm weather? There is no direct measurement of humidity, so the pcm can not directly correct for that. The IAT will(should) correct for temp differentials. How well it works in practice depends on how good the GM calibration is (very good) or if you tuned the car yourself how good your tuning is.
Chris
Chris
07-16-2002, 05:28 PM
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Re: if car is tuned in cool weather, will it run rich at the track in warm weather? My car did just the opposite. Had the car dyno tuned in early April. About 60/65 degrees outside. Now the warmer weather gets here (90's) and I start to get KR. Up to 4 degrees. I then had the guy that did the dyno tune check it out and he made some adjustments and all is better now.
We actually took the car out and ran the crap out of it to see what was happening. He made minor adjustments each time till we where happy.
Can definitely feel the difference on the street now. It seems to pull a little harder. Dyno Tuning is great but also I think taking it out on the street to put a load on it helps in fine tuning it as the dyno can not really simulate the load the car will hve on the street.
Just my .02
- Tom <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
We actually took the car out and ran the crap out of it to see what was happening. He made minor adjustments each time till we where happy.
Can definitely feel the difference on the street now. It seems to pull a little harder. Dyno Tuning is great but also I think taking it out on the street to put a load on it helps in fine tuning it as the dyno can not really simulate the load the car will hve on the street.
Just my .02
- Tom <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
