Ok, now i know when your racing in the summer it is better to turn off your ac because it robs power from the engine, but during the winter when you want to race should you leave your heat on or turn it off. wouldnt you want to leave it on because it takes heat away from your engine meaning more power?

 

Yeah, also, the heater doesn't use very much power compared to the AC compressor.

 

I'm actually going to do a GTECH run tonight. Too bad you really can't duplicate the same launch each time. Otherwise we could test the theory. But I doubt it makes that much of a difference. You can leave the heat on. But it won't exactly cool the engine. The outside air rushing in does a better job.

ZuM

 

But bear in mind, there is almost no parasitic horsepower draw from the heater core. The heater being on would only serve to lower the coolant temperature a bit...this is why they say to blast the heater if your car overheats in the summer. But since your racing in colder temps, it's not an issue.

If you turn your defroster on...there might some issues...because I suspect that the defrost function turn the AC compressor on.

 

It really doesn't matter. The engine creates heat and must transfer it to the atmosphere to prevent overheating. When you run your heater, some of that heat goes into the indoor atmosphere (via the heater core) and the rest goes to the outdoor atmosphere (via the radiator). If you turn off your heater all of the heat goes to the outdoor atmosphere.

 

in drivers ed they say if your car is about to overheat turn on your heater full blast cuz it vents the hot air from the engine into the car making it cooler for the engine... then i asked why would it matter if it would only make about a .5 degree differnce then they said get out... reason for kivking me out, never got one...

 

I guess you may want to do it if you're trying to squeeze every bit of performance you can get out of the car. Before my gtech runs. I had my sunroof and back windows open with my heater blowing full blast.. =) If anything, it kept me warm and I was able to enjoy nice cool outside air. I think its just psychological. That way I don't go.. Oh, what if I could have run faster if there wasn't so much heat trapped in the engine bay. Etc. Might not be an issue with CAI people. I dono.

ZuM