monicle

I recently swapped out my stock gsr manifold with a skunk2 manifold and used a hondata heatshield gasket as well. since then I have seen a noticeable difference in my exhaust temps. they seem to be on average several hundred degrees cooler for some reason. I am using hondata for my fuel management so its not like the ecu would have reset the fuel tables or anything. Can anyone shed some light on this for me? Shouldnt I have noticed a change in performance as a result of the drastically lower egt's?

fjt

Well i know the Hondata Gasket will make the air ingested into the engine cooler but i dont know if it has and effect over the EGT's..

monicle

yeah i could see that if it affected it by mabe 100 or so degrees give or take. but its changed quite a bit.

PM-Performance

changing the manifold and gasket is prob making you run leaner. check the a/f's. that could be the reason for the EGT change

monicle

if i was running leaner I would expect a higher egt reading though.

-Trinitron-

Is your intake air temperature sensor on the intake manifold? If so, it probably isn't getting as hot. So it is adjusting the fuel for the air temp being cooler. That would make you run a little richer causeing your egt to be a little lower...i think...

PM-Performance

i forget how the hell the EGT's numbers go in reguards to A/f . i would think the car would be running a little leaner though due to the part you put on and the denser charge.
Actually i think Leaner might be higher EGT's my fiances dads Cobras was high EGT on idle and it was idling dead lean. So i dunno then.

-Trinitron-

it should add fuel for colder charge...more dense air requires more fuel. since the air temp is actually the same, the computer is "tricked" into adding more fuel.

monicle

hondata doesnt fluctuate the fuel tables as far as i knew (i no hondata guru). so i figured it wouldnt change no matter what you threw at it. correct me if im wrong but the fuel should be exactly the same as it was before.

-Trinitron-

it has to compensate for air temperature. otherwise you would run extremely rich in the summer and extremely lean in the winter. There would also be no need for the intake air temperature sensor. If the sensor is cooler, it thinks the air is cooler.

monicle

ah good point. yeah the iat is still there but the hondata gasket would decrease intake temps slightly. again though it seems like it changed alittle much. Ill have to go by some time on the dyno again and see how things look.