Intercooler Placement IDEAs Needed., Need a better option.....Love my water to air, but open Options

[budman5201]

As all you probably know, i have a ej20 turbo subaru in my car. I love it and it runs great, but now i am at the point where i want to streamline how well the system works.......

First matter of attention is the intercooler placement. I have a small water to air intercooler tucked in front of the pulley on my subaru motor. It works great, but i am getting a little too much heat soak on the aluminum tubes leading to it. I was debating an idea of putting it in the rear trunk or in the fender since placement wouldnt be a factor because its a water to air. I do like the one members ORANGE nice turbo car on 914world here with the air/air one in the back and vent in the wing.....

Looking for ideas....

[DBCooper]

All true, except Budman's car has a watercooled engine and no more engine tin, meaning the air will flow through the engine compartment basically without impediment and probably from high pressure to low. That makes the student's statement "The results of the engine compartment were consistent with the expected result. Air flowed up through the compartment for all configurations" very curious. Curious because their professor's car was aircooled, meaning air flow through the engine compartment could only have been top to bottom, from the cooling fan intake above to hot air exhaust below. This is from the presentation summary and I didn't see a link to the full report, so maybe the "for all configurations" is explained better there.

I'm interested because my car has the same WRX engine with an aftermarket air/air intercooler on top. It's a little different in that I vented the IC opening like this:

(IMG:http://i379.photobucket.com/albums/oo234/paulillick/IMG_0012-1.jpg)

In the future I intend to replace the expanded metal on the lid with solid metal, sort of the reverse of doing a GT lid, so the only opening will be for the intercooler. Then I'll do my own tuft testing to see which way the air is being drawn through the engine compartment (high pressure to low) then add a spoiler or two to "encourage" more of that natural flow. For example if the air is flowing up because the lowest pressure is being created by the drop of the top behind the rear window I'll try to increase that flow by putting a little duck tail on the rear of the targa top to create more low pressure there. If it's flowing downward I'll try to increase it by putting a flexible duck tail across the bottom of the car just below the front of the engine compartment. With the closed decklid the intention is to channel all the top to bottom or bottom to top airflow through the only opening, which will be that intercooler cutout.

I'm looking forward to seeing how the flow with fans works out. Just in case. In the meantime I've limited boost to 10 lbs. Also just in case.

[ottox914]

In the future I intend to replace the expanded metal on the lid with solid metal, sort of the reverse of doing a GT lid, so the only opening will be for the intercooler. Then I'll do my own tuft testing to see which way the air is being drawn through the engine compartment (high pressure to low) then add a spoiler or two to "encourage" more of that natural flow. For example if the air is flowing up because the lowest pressure is being created by the drop of the top behind the rear window I'll try to increase that flow by putting a little duck tail on the rear of the targa top to create more low pressure there. If it's flowing downward I'll try to increase it by putting a flexible duck tail across the bottom of the car just below the front of the engine compartment. With the closed decklid the intention is to channel all the top to bottom or bottom to top airflow through the only opening, which will be that intercooler cutout.

I'm looking forward to seeing how the flow with fans works out. Just in case. In the meantime I've limited boost to 10 lbs. Also just in case.

Interesting thought, closing off the grilled section, could result in a smooth, cool. custom look for the back of the car. You'll gain a bunch of IC cooling if you can duct the opening in your engine lid to the intercooler. Air will take the path of least resistance, and right now, assuming your airflow is top down, that would be thru the hole in the lid, hitting the IC, and rolling off the sides. True, some will be going thru the IC, but you're loosing alot of flow around it also. To duct the cooler to the lid, and add fans and a plenum below (assuming you have the space) to push/pull, whatever you determine is the correct direction of airflow for that motor in that car with that IC set up, would make for a more efficient IC. I was going to just mount my fan to the back of the IC, and a couple friends, one who is the leading HVAC guy in our town, and another who works for CAT designing IC systems for their earth moving equipment, both got all over me for not using a plenum on the back of the IC to better direct the airflow thru the intercooler, rather than just have the fan blow air at the intercooler. The CAT guy was showing me testing data that where the centerline of the blades was in relation to the plenum was, so in effect mounting the fan on the back of the plenum, inside the plenum, or with the blades even with the back of the plenum would have a measurable effect on the cooling ability of the system. A little to picky for my little project, but shows that having the plenum/ducting makes a difference.