Has anyone ever thoought about connecting freon to the throttle body heat lines?
It wouldn't be worth it in its own right, but it might gain back a little of the parasitic loss of the A/C compressor when it's in use.

Hey, I just noticed we have some new smilies (graemlins?). I wonder if this works: :mbs:

actually, i think it would be TOO cold. the throttle body only plays a small part in the air induction system. most people bypass the coolant hoses going in it to keep it cooler. keep in mind this IS a direct port injection motor. how would you circulate the freon? also, there are alot of issues dealing with the chemistry of freon that just would not work out. i don't think the effort would be worth the reward. kind of like those "ice canisters" for drag racers. i think that's just a bunch of hype.

I'd think the TB would ice over very quickly...

Putting a cooled heat exchanger (intercooler with active cooling? especially on a high boost forced induction motor, that might be intresting!

Best!
Ben.

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Ben Cannon
88 Formula, T-top, Metalic Red. "Every Man Dies, not every man really Lives"
88 Formula, Northstar, Silver, In-Progreess. -Mel Gibson, "Braveheart"

Well, just running freon through those coolant pipes won't do it. You need a metering device and an evaporator to get a cooling effect. Freon only cools when there's a pressure drop, and flowing through the pipes would be at a constant temp.

Also, icing is a concer, obviously, and if the throttle body is the only part chilled, the air moving through it won't be in there long enough to be cooled.

Now, a freon chilled intercooler for a turbo could be interesting. Chill the intercooler down before a race, then turn off the AC during the race. Not very useful in everyday driving, though.

I saw someone in one of the car magazines do something similar on a Mazda Miata. They made some sort of air intake intercooler with the AC and tested on the dyno before and after. They actually picked up a couple of HP over the parasitic drag of the AC compressor. I think they said something like 5 HP. I also remeber them saying something about 1 HP gain for every 10 degrees you cooled the air or something like that.

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Okay, now for an engineer's opinion. Air has a very low specific heat. Therefore it takes a lot of surface contact area to exchange heat. There simply isn't enough surface area or residence time in a throttle body to significantly affect the inlet air temp, nor is there enough surface area to HEAT the air up, even 1 deg. IMO THE THROTTLE BODY SHOULD BE HEATED. Why? Because air flowing through an orifice expands. The manifold is under vacuum. Expanding air cools. In cold weather, with air near the dew point, this minor expansion is enough to drop the temp below the freezing point. If ice forms on the throttle plate it can lock it open. And you know what that would cause.

On a car like the Fiero probably enough heat is conducted through the aluminum manifold that this is a minor problem, except in very cold and damp areas. However on an engine like a N* or LT1 with a plastic manifold there is virtually no heat transferred to the throttle body. These TBs should always be heated.

A throttle body isn't like a carburator, There is no gas present. Weither the TB is hot or cold will have little effect on the performance of the engine.

Now if you can cool the incoming air charge, that would be dirfferent. But this would take a cooler like an interchanger. Remember, a turbointerchanger is BIG and it only gets a 50 deg or so drop with ambient air. It's effeciency can be improved by having a greater delta T, such as a Freon cooled air charge. This would be very expensive and require a lot of plumbing. Go with NOS.

IT HAS BEEN DONE
BUT IT DOES NOT WORK VERY WELL
at the first Miami GP IMSA race I was in the pits BSing with a crewman befor the race
He had used a A/C unit to cool a turbo
in a old ford crapi He said it worked for one gear but by the time you were ready to shift to second gear the A/C unit was TOOOOOO hot and could not keep up with the heat load the turbo put on it.
and drag of bigger unit would be tooo much and add weight too if big enuff to work.

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Question wonder and be wierd

If you've ever iced up a throttle body, it's a very high pucker factor event......

I never have iced a TB but I know someone with a N* in Washington State who from his symptoms sounds like he did. Throttle stuck at 2800 rpm. Bummer.