intake temperature problem

[2000saleen]

i have a 2000 saleen mustang which is only dynoing at about 305 hp right now, it's supercharged and stock runs at about 350 hp i had it dynoed a year ago and it dynoed at 390 hp. when hooked up to a computer it shows that the intake temp. is about 170-190 degrees and it should only be about 90, so i'm wondering if the problem could be that the A.C.T. sensor is mounted on the block and is reading the block temperature, or if my supercharger isn't working right or what my problem could be if anyone has a 2000 saleen is the a.c.t. sensor supposed to be mounted to the block, because on the new cobras it's not and the sensor is actually after the supercharger and not before.

[Jeff Chambers]

If the ACT (IAT) is mounted after the supercharger (the best way to mount it), then your intake air charger temperatures are correct, especially if the car has no after/inter cooler. I don't know who told you that your ACT should only be 90-deg, but their wrong. Even with a methanol boost cooler setup its tough to get IAT any cooler than 110-deg under boost. The only way that it would be reading that cold is if you're using a six-wire MAF or a separate IAT sensor located in the intake tract upstream of the supercharger.

[2000saleen]

well it is intercooled, and the sensor is mounted before the supercharger and saleen is the people who said the temp should be around 90 and that every degree over 90 is making me lose approx. 1 hp in certain power bands. so i'll just keep trying to find out the problem. but thanks for you help, i think i'll try to just move that sensor first.

[Jeff Chambers]

OK, so the IAT is mounted before the supercharger. If that's the case, then there is something happening with the sensor. Before the supercharger it should read approximately the ambient air temp plus some small delta for the engine heat its picking up from the filter/inlet to the point of the sensor. Try swapping out the IAT sensor. Is there a secondary air charge temperature sensor after the supercharger/intercooler? The PCM is going to pull timing and add fuel as the air charge temperature increases. Are you by chance looking at the secondary sensor output? You need to log some additional PIDs such as spark advance, spark source, borderline knock, MBT spark, STFT and LTFT to try and really figure out what's going on.