I was looking at the throttle body and all the stuff that is hooked up to it and something caught my attention. It looks like the throttle body has coolant running through it, correct?

If it does that brings me to some questions. Why does the TB need coolant going through it? Wouldn't it just warm the air back up after the intercooler?

I'm guessing it has something to do with emissions, but since I will never take the car through that is there anyway to bypass this? It looks fairly simple. Just wondering if anyone has done this or thought the same thing. If not I will be the first one to try this I guess and will post the results if there are any.

Mike

 

Yup

I'm sure there is a way to bypass it, as us fbody guys have been doing it to our ls1's as one of the "free mods". The gains would be minimal though.

 

Thought so... I did the same thing to my ZX and it had really no affect either.

 

It is to prevent the throttle body from freezing. If you live in cold climates, then you should not bypass. The gain is minimal (2 to 3 hp and a little faster throttle response) and not worth the hassle for most warm climate Evo's.

Speedlimit....

 

I heard the anti-freezing thing in cold weather too.

I used a Hondata Insulating gasket for my S2000, and I heard rumours that Hondata will make one for any car, if you send them the original gasket.

Might be worth a shot?

It made a difference only in start/stop traffic for the Honda. There were no measurable gains on the dyno, but then again, the dyno doesn't simulate standing still in traffic.

 

OK people, it has nothing to do with freezing or with emmissions!

The throttle body has a Fast Idle valve that is basicly a wax plug. When cold the wax contracts alowing an air passage to be opened up giving you a lot of air flow in cold conditions for a fast idle during warm up. As your coolant gets warm from idleing the coolant running thru the throttle body warms up this wax plug causing it to expand and block off this extra air passage. At this point your idle speed drops off toward normal.

Keith

 

Wax plug? That doesn't sound too reliable...

Thanks for correcting our stupidity

 

You are correct, it ISN"T reliable What did you expect from Mitsubishi?

They tend to either dry up with age and not seal giving your a permenently high idle.... or get gummed up and stick closed giving you a slow idle when cold. In general, they suck! But they are cheaper than making a larger motorized bypass valve. The small motorized bypass valve we have is only large enough to compensate for idle changes due to load such as the AC compressor and power stearing demands.

Keith