so i searched and i could not find a thread that thoroughly explain heatsoak. i read a couple threads referencing it, and some vaguely saying what it is, but i still dont have a clear cut understanding of how it effects our turboed cars. someone please chime in.

thanks.

 

Well most people refer to the intercooler when talking about heat soak. It is when the intercooler itself becomes hot and does not cool down enough causing any air that enters it to also get heated up as a result of it being hot. Hope that simple explanation helped.

 

yep it gets hotter and doesnt cool intake charge air as it should!

 

so pretty much an intercoolers job is to take hot air, compress it, and make it cooler right?

so then with heatsoak, the hot air goes in, compresses, but doesnt come out any cooler?

also, if that is the case, how much does it effect the car's performance.

 

An intercooler will not compress any air, its just a tube of heatsinked fins to disperse heat and let air flow through it. With heatsoak, its just too hot due to long use or ambient temps to provide any further cooling or at least negligable amounts of the said.

 

actually the Intercooler takes the high temperature and high pressure air and cools it but does not (typically increase pressure). As the temperature goes down the air becomes more dense and therefore provides more oxygen per volume of intake charge.

as the I/C becomes heatsoaked, it can't cool the air as much (at all) and the less dense air enters the intake and is burned. this air has less O2 to burn and therefore the car makes less power.

this is why the water sprayer is effective, because the water works better at wicking heat away from the body of the I/C and allowing it to be closer to ambient temperature, thus maximizing the temperature difference between I/C body and the hot charge air.

 

oddly enough, this actually makes sense. anywho, is there anywho to know how heatsoaked your intercooler is at any particular time? other than putting your hand on it and saying "hot hot hot"

 

the easiest way is to feel the temp of the intake pipe before the throttle body. If the I/C is not heat soaked, the temperature of this pipe will be close to ambient temperature.

 

is there a guage out there that can measure this? i mean we have an EGT, i would think that heatsoak would be just as important right? cause during the summers here in socal, i want to know if im losing power or what not? and if i should let my car rest at times.

 

I wouldn't think it would be much of a gain. I have a smaller I/C than the stock evo one on my rally car, and I don't ever have a problem.

 

I have a couple aircraft quality intercooler inlet/outlet temperature gauges made by DavTron if anyone's interested in doing some real world testing...