Somebody check my theory

[93anthracite]

Ok, I've always felt that big intercoolers and big radiators never really needed huge front openings to feed them, which is one of the big lessons I feel was demonstrated at the testing. In fact, apparently you need area 1/4 the size of the radiator, or less, to work efficiently.

For the turbo guys, your intercooler needs air too to cool the charge. I've never liked the idea of an IC sitting in front of my radiator blocking cold air to a much more critical component. So I had a thought...

Why not have an radiator that fills 1/2-2/3 of the radiator crossmember and fill the rest of the crossmember with an intercooler and oil cooler? You should be able to have a smaller air opening and with good ducting using the diagram below, force air through each component, instead of stacking them to make air go through all three.

________________

l . . . . . . . l . IC . l

l . . RAD . . l------l

l . . . . . . . l . OC .l

 

 

Many early 90s hondas do this with their radiator and AC condenser, IIRC.

 

My other question is how a V-mount setup might do, though I feel ducting might be a little more complex to be effective on our car, and I don't think there is enough room, unless you get rid of the fan.

 

edit: crap, it didn't like my diagram, ignore all of the periods

[OlderThanMe]

You may not need the same intake size but you will probably still need the same size intercooler and radiator as normal.

This is explained in the book "maximum boost" by Corky bell.

[93anthracite]

meh, that's been sitting on my shelf for months, hoping I'll get around to reading it one day. Thank for giving me another reason that I should actually pick it up

[johnc]

You're confusing cooling system capacity with radiator air flow requirements. Just because air flow requirements for a standard sized 240Z radiator can be met with a much smaller grill opening doesn't mean the radiator can be made smaller.

[Mikelly]

Here's another thought... I spoke with the folks at Griffith and Ron Davis Radiators a while ago, and both said to get away from larger sized radiators, but to retain cooling capacity, go with larger diameter tubing (1-1.25 inch) throughout the core. So you'd make your radiator thicker, but take up less space, and retain much of the cooling capacity.

 

And I'm with you on the "smaller intercooler" thing. My radiators on the 996TT are small in size, but I have two, and I have 8 GALLONS of coolant to help shed heat. My intercoolers are TINY and stuffed inside the rear hips of the car, behind the rear wheels. It's making 510WHP and 532#ft. of torque at the wheels and doesn't run hot... I'm thinking you're onto something John!

 

Mike

[johnc]

What most folks forget is the primary coolant on any car is engine oil. Cooling the engine oil efficiently reduces the load on the secondary coolant - water/anti-freeze. I'm betting that Porsche has a very efficient oil cooling system as part of its dry sump setup.

[Mikelly]

Probably so, along with 9 quarts of oil in that dry sump system. Who knows.

 

Mike

[93anthracite]

ok, I'm back with a little more knowledge. I looked for a few minutes at Corky's book and taking into account Mike and John's input, hopefully I can put my thoughts into words.

Based on the turbo book, you only need frontal area of about 1/4 of the intercooler for pretty good efficiency. Surprise, that's exactly what we found for the rad as well.

I looked back at my last post and realized I hadn't really elaborated. I surely wasn't intending on grabbing a tiny, 1/2 inch radiator from a Honda and slapping it in there. I was thinking more of having a custom rad. made about 3 in. thick, but just not as wide. This should allow for almost the same amount of coolant to be in the system. That huge difference in fluid over the Honda unit, if nothing else, provides a larger heat sink to let the heat spread over and thus take longer to actually raise the temp (meanwhile being cooled in the radiator).

Like John said, the oil is the primary cooler, which is why I put a rather large oil cooler in there to compensate for the smaller radiator. A big intercooler doesn't really do it for me, so it got the leftover space.

Thoughts? I'm really just trying to figure out a way to make a compact but efficient use of an intercooler, oil cooler, and radiator.