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Old 06-17-2012, 11:41 PM   #1
vex
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Default Radiator ducting

So I've heard a bunch of a different things about this. I am looking for material or basics on radiator ducting. In particular the intake port size based on radiator size. I have heard everything from 25% area, 33% area, or 1/6 the height of the radiator. Another thing I'm curious about would it be more effective to duct directly through an intercooler to oil cooler and finally to a radiator or if it would be more effective to duct the intercooler and oil cooler and plumb fresh air through a scoop?

Here's a digital mock up of my particular setup and a possible version with a scoop. The plan is to duct them to be air tight between the intercooler (green) and the oil cooler (yellow) while allowing additional mass and colder air to be pulled in for the radiator. Ideally I would have liked to duct each individually and allow for fresh air to be directed on each.





Here's about the only thing I have found online recently:
http://ecomodder.com/forum/showthrea...or-6439-3.html






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Old 10-17-2012, 03:40 PM   #2
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Ever come up with anything? I've been reading around the Improved Touring forums and the general impression is to not have the outlet of one heat exchanger leading to the inlet of another and that ducting so no air can bypass a heat exchanger is critical. Just curious if you made anything because I'm scratching my head trying to come up with something for my FC.
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Old 01-18-2013, 08:25 AM   #3
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I wanna bump this to see what everyone else is doing for ducting: how they're set up and what materials are being used.
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Old 01-18-2013, 10:19 PM   #4
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i used DiBond for mine. Lighter/stiffer than plain aluminum sheet, although alumacore is probably better.

There's no 'science' involved in my setup, other than (mostly) sealing the front of the radiator. The front of the duct isnt properly sealed to the bumper because I am lazy. but that would be better.


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Old 01-22-2013, 02:44 PM   #5
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^^^ So you completely cut out the stock radiator cross brace and everything? Did you also remove all the front bumper cover support or is it just removed for the pictures? Unfortunately I still have all the crap in the way, but I have lowered the OEM oil cooler so its bottom is level with the radiatior's. What are your thoughts about ducting the "exhaust" of the oil cooler away from the radiator?
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Old 01-23-2013, 11:19 PM   #6
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yah i got rid of all that crap. ducting looks like a PITA with all the stock metal in there.

out of all the pieces that cross the car, i only kept the triangular one (top of rad mounts to it) and the bumper mounting flange thingy. both are pictured above.

also got rid of all the headlight garbage in the process, and used some cheap plastic autozone lights :P
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Old 01-23-2013, 11:21 PM   #7
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regarding the oil cooler- i just mounted it (and the fan) on the hot side of the radiator (its a single pass). i didnt want to vent into the wheelwell, and i didn't really see any other good place for the cooler. both cool fine as is, its not like i'm pushing any limits with the heat exchangers or anything.

top view might help-

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Old 01-26-2013, 02:03 PM   #8
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What's the Dibond like to work with? What gauge sheet did you go with?
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Old 01-27-2013, 12:17 AM   #9
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i dont know what thickness i used, i used scrap i found at a shop. the stuff is really easy to cut on a bansaw. scoring with a knife was pretty hard, but doable (it is aluminum afterall). beltsander worked great for cleaning up edges/corners. overall very cool stuff.
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Old 04-04-2013, 01:41 PM   #10
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Bumping this once more. Would there be a benefit of running the radiator and oil cooling in a "v-mount" setup over the stock series setup? In a v-mount setup is it more efficient to have both heat exchangers angled or would it still work well enough with one parallel to the ground? I'm thinking about leaning the stock oil cooling down so it seals with the bottom of the radiator. This would obviously require a little fabrication but would simplify the ducting.
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Old 07-30-2013, 02:44 PM   #11
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Quote:
Originally Posted by josh18_2k View Post
yah i got rid of all that crap. ducting looks like a PITA with all the stock metal in there.

out of all the pieces that cross the car, i only kept the triangular one (top of rad mounts to it) and the bumper mounting flange thingy. both are pictured above.
Bumping this again with a question.

So I assume you cut out the round bar the connects the frame rails near the front of the car? This is the support from which the oil cooler hangs. Without that ducting will be much simplified but I don't know how critical it is to chassis rigidity. Would a small bar like you have where the stock bumper support was bolted be enough?
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Old 07-30-2013, 10:46 PM   #12
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Yes I cut out the round bar. It's just spot welded in, and it doesn't triangulate anything. How structural is it really? I dunno, but it's in the way. Plenty of people cut off their entire front ends forward of the strut towers. Cutting it off won't make a noticeable difference. My car is plenty fast without it. Besides, a strut tower bar will do way more than anything mounted in front of them.
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Old 08-12-2013, 04:29 PM   #13
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Here's how I did some ducting for my oil cooler, maybe it'll give you some ideas. Had high oil temps with the front mount. Haven't got oil temps over 180 driving around in the summer, before they would easily get over 200. Also helped lower the coolant temps a few degrees, but never had high coolant temps before adding this ducting.
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Old 08-13-2013, 07:37 AM   #14
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Quote:
Originally Posted by josh18_2k View Post
Yes I cut out the round bar. It's just spot welded in, and it doesn't triangulate anything. How structural is it really? I dunno, but it's in the way. Plenty of people cut off their entire front ends forward of the strut towers. Cutting it off won't make a noticeable difference. My car is plenty fast without it. Besides, a strut tower bar will do way more than anything mounted in front of them.
I got really close to cutting out. I stopped when I realized I would have to make new oil cooler lines. Mine are already stretched pretty far because I lowered the oil cooler about 2 in. so its bottom is even with the bottom of the radiator. What I've ended up doing is relocating all the wiring up underneath the upper radiator support and I've since cut off all the brackets on the oil cooler support. So it's still there and still annoying to get around but it's a lot less intrusive than it once was.

Quote:
Originally Posted by antman0408 View Post
Here's how I did some ducting for my oil cooler, maybe it'll give you some ideas. Had high oil temps with the front mount. Haven't got oil temps over 180 driving around in the summer, before they would easily get over 200. Also helped lower the coolant temps a few degrees, but never had high coolant temps before adding this ducting.
I was wondering if anyone cut out the "spokes" and center of the lower bumper. I'm considering doing that too as I've also got an ISC splitter, which gives about 1.5 in. more height for the oil cooler/radiator inlet. Are you still using the stock undertray as well? I'd think you'd have to to avoid air rushing around the radiator.
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Old 08-13-2013, 08:13 PM   #15
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Quote:
Originally Posted by infernosg View Post
Are you still using the stock undertray as well? I'd think you'd have to to avoid air rushing around the radiator.
I am. Had to cut it up a little to bolt it on.
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