Intercooler and radiator placement

This "horsepower wars" thread, and specifically the image of the twin turbo engine with the huge IC directly in front of it with about a foot between IC and engine just made me wonder...

What's ideal? What's the norm? What can you get away with?

Are they really just mounting an IC the size of a radiator in front with the rad right behind it? How much heat's coming out of the IC, and does it have much effect beyond restricting airflow to the radiator?

If I had the time, I'd google for how much heat energy winds up in the intake air and how much the IC is probably actually heating the air which is cooling the radiator, but for now I'd be happy with "yep, that's how it's done" or "no, that's crazy business."

The 2002 may need an IC, and it'd be swell to be able to tuck it into the nose box ahead of the radiator rather than trying to put it an air dam or something...

ransom wrote: What's ideal? What's the norm? What can you get away with? Are they really just mounting an IC the size of a radiator in front with the rad right behind it? How much heat's coming out of the IC, and does it have much effect beyond restricting airflow to the radiator? If I had the time, I'd google for how much heat energy winds up in the intake air and how much the IC is probably actually heating the air which is cooling the radiator, but for now I'd be happy with "yep, that's how it's done" or "no, that's crazy business." The 2002 may need an IC, and it'd be swell to be able to tuck it into the nose box ahead of the radiator rather than trying to put it an air dam or something...

From what I know, there really isn't an ideal outside of trying to cool the charge air down period. As long as the radiator has SOME flow, it will stay cool. Reason being look at diesels, they run the same setup and they cool just fine, both radiator and charge air.

In front of the radiator is the usual position - first thing in the radiator stack. It doesn't put out as much heat as a radiator and I'm not sure how much heat it then dumps into everything else, but it seems to work fine. Of course avoiding radiator stacking is ideal but a big packaging & aero challenge.

The usual order in a heat exchanger stack, from first to last, is: PS cooler where present (sometimes just a tubing loop, deals with very little heat), Intercooler, AC condenser, radiator, oil & trans cooler (no need to stack these two small things).

And don't forget V-mounting (putting heat exchangers in two stacks on the front of a car, like the lips of a pac-man mouth).

Also in the pic linked from the thread in the original post, there would be a radiator behind that intercooler setup. Don't know if that is obvious or not.

I put one infront of the radiator and it overheated. I guess the total opening was too small.

I was working at the sign-in station for a stage rally once and an RS200 rolled up, now you see the two mesh things under the spoiler here:

It didn't have those. All that stuff under there was cut out and it had some kind of heat exchangers there (looked like intercoolers, there were two of them on the sides). And then it also had an extractor hood, when it rolled up the heat was INTENSE.

Its generally always wiser to put the I/C in front of the radiator. The IC is air/air which is far less efficient than the radiator which is air/water. That is to say; giving the radiator hot air from the IC doesn't reduce its heat shedding much. But, if you turn it the other way around, it will not be much benefit to the radiator but it will dramatically reduce the IC's ability to shed heat.

I'm sure there are many situations where putting the IC in front causes coolant overheating, but its usually able to be recovered with small improvements; upgraded water pump, better fan, double stats, etc.

There was an interesting article I'd read about one of the most merciless applications out there for getting heat out of a turbocharged engine. They had opted to put a radiator and an intercooler side by side, equally sized, with other coolers in front. Found that worked better than anything else.

Their worst case application, in case you were wondering, was a tractor. Limited packaging room, runs a fairly high amount of boost, for hours on end, with one mechanical fan... at six miles an hour the whole time. Not an easy turbo motor to cool.

if I may hotlink from one of my book of faces photo albums...

problem solved. maybe.

It would be cool if that intercooler had flexible hoses and could be made to pop up and retract like a sailplane's spoilers

Maybe if I'm really lucky I can get an IC perched in front of the top of the radiator in the 2002's characteristic nose...

Local rally car with Serious Business intercooler:

got any wallpaper sized shots of that rx3 by chance...

I think I just found my new desktop wallpaper at work.

Only other decent pics I can find:

what a great conversation... I was about to get a front mount for my saab... this answers some questions