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2002 WRX 4EAT: Best Locations For Trans Cooler Without A Fan?

4K views 15 replies 3 participants last post by  Jackstand Johnny 
#1 ·
Hi everyone. I have a stage 2 bugeye WRX with the 4EAT automatic transmission and after my final engine upgrades and upcoming protune, Im going to focus my attention on the auto trans. I will be installing a cooler(looking at the Hayden 677 or 678 but the size will be dictated by the best mounting location) and Im hoping at least one person here has done this and can give me some guidance. Heres some details:

-Im running a Koyo OEM style radiator that already has a built in transmission cooler because its modeled after the factory 4EAT rad.
-Yes Ive given this a lot of though and I am sure I need an auxillary transmisssion cooler
-No this wont be the only upgrade or modification done relating to the transmission. For the sake of this particular query I want to focus on the subject of an aux cooler.
-My WRX has 107k miles and so far this transmission is holding up, I want to keep it that way.

I want to know what size cooler I should run(I dont think bigger is better in this instance but I could be wrong) and I think finding the space to mount a cooler is going to be limit my options anyways. I do not want to mount it in front of my radiator. Its a factory spec rad and needs every inch of cooling surface it has so I dont want to take away from my engines cooling capabilities for the sake of the transmission. I plan on running this cooler in conjunction with the built in stock cooler and Id like to mount the aux cooler somewhere in the front half of the car in a place where it will get plenty of air but also in a safe place where it wont be in danger from debris or the potential ditch, curb etc lol. Basically I want it sitting no lower than my exhaust.

Possibly a tall order and I might be trying to have my cake and eat it too but not impossible, right? Im also looking for any other plate and fin style coolers so if you have a better one thats $60 or pess please let me know! Thanks in advance.
 
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#2 · (Edited)
core:


mounted:



do this but on the opposite side. this is my engine oil cooler.

i too will be adding a transmission oil cooler (this exact one by B&M) and its going in this same spot but mirrored other side. and your trans oil lines are already routed to that location.

the stock brake duct was cut a bit to allow a little air flow during normal driving. and when at the track, just remove your foglight (or light cover) for a full on ram scoop going straight to your cooler core.

*edit*

i just remembered i have a JDM front bumper beam. dont know if there is the same amount of room with the USDM front bumper beam
 
#3 ·
In front of the wheel well opposite your oil cooler is one of the best spots you could run it. Only downside is depending on how much of the OE plastic fender guards you have those may be relatively devoid of airflow so cooling fans might still be a good call.

I've seen some really cool top mount oil cooler solutions that use the OE inter cooler position for oil coolers, the brackets dont care if your running engine oil or trans fluid through them and I could definitely see you running both side by side in that top mount position if you have a front mounted inter cooler or you plan on going that route. The top spot would be open and aerodynamically tuned for a cooler already.

It might be a dangerous idea ( as far as flying rocks and bits at the track ) but if you plan on only using the car at the track you could pull your fog lamps and leave those holes open, or cover them with mesh to increase flow over the oil and trans cooler in the OE location.

If you dont mind why no fans? They have relatively low power draw and they increase the airflow over parts when the car is done with your run when they really need help cooling down.
 
#6 ·
Thanks everyone! I dont ver plan on going fmic. I didnt want a fan because I want to keep this as simple as possible. I want to rely on natural air cooling by finding a good location rather than relying on a fan. If the fan dies and I dont realize it but am relying on it for cooling then it could be a waste of a trans cooler. Id also like to keep my hella 500 fog lights in place. Ill take a closer look at all of these. I really like the idea of modifying a fender guard or duct to direct airflow. I wish i had a way to calculate airflow under the car while driving. Thanks so much again guys keep em coming!
 
#9 ·
Yes thats always been a big problem here. My parents live on what used to be a farm and theres a LOT of gravel and dirt around here. My entire driveway is gravel. This cooler will need to go in a safe location. Ive been really procrastinating on building this stainless steel skid plate(I just happen to have SS sheet laying around so thats what Im using) because the plastic splash tray is a joke. I wonder if there is a way to make a shield for this cooler out of SS sheet or even better would be to somehow mount the cooler so I could just incorporate louvers or something on this skid plate so it will direct air to the cooler while still protecting it better than nothing at all. Kinda like the eye slits on a knights helmet haha.
 
#10 ·
thats exactly what i mean by "air ramp".

couldnt think of the word at the time, but we cut 1 big louver in the plastic to direct airflow to my cooler core.

i wouldnt recommend doing this on a skip plate because if you hit a puddle you could scoop water at high velocity into your engine bay. not a serious problem as its just water, but with enough force it could knock something loose.
 
#11 ·
Thats a good point. Theres gotta be a way though. Its like a puzzle. I mean, arent there several skid plate designs with air ventilation holes slots cut in them to help cool things down? I could have sworn Ive seen a few like that. Then again just because theyre out there doesnt mean its a good design or doesnt have flaws lol.
 
#12 ·
it can work, you just cant have the louvers facing forward. have them facing rearward and they act like an airplane wing sucking air out via low-pressure zone.
 
#13 ·
My crotch is a low pressure zone. All seriousness aside thats a really good call. Louvers facing forward would basically be like tiny shovels scooping up rocks and debris. I could always get a little fancy and put a mesh grill behind whatever opening or scoop I make. This is all looking like its not gonna happen real soon now anyways. I really wanted to have this done before the end of summer but...hahahaha...thats not gonna happen unless some real good luck comes my way and I think I used up all my luck driving through town with an open downpipe to get the exhaust fixed. I know its only $50 but Im broke and a guys gotta eat.
 
#14 ·
Do you think Id be able to mount my cooler where you mounted yours without habing to take off my front bumper skin? Ive never done it and Id like to do this in stages and not tear my daily driver apart. If I can do what you did without removing my front bumper then I want to do this in stages. Like cutting the fender liner, fhen cut up and river the flap down for the air scoop. Then find spots for the mounting brackets and then finally, run the cooler lines and mount the cooler. Its very hard for me to work on my car for extended periods of time so pulling the bumper or doing this all at once would really really suck and might leave me without a car for a couple days. Thanks in advance everyone!
 
#15 ·
you'll need to pull the bumper. take your license plate off and zip tie it to your bumper beam so you can drive around without a bumper skin if you need to. pretty sure thats still road legal. (it is where i am) if you cut the fender liner you will get rocks and crap flying onto your new cooler potentially damaging it and also fling rocks into your engine bay.

pulling the bumper takes literally 30 seconds once you have done it a few times. mine has been off and on im debating quick release drift latches. the hardest part is finding all the clips. there 2 or 3 on the bottom undernearth and another 1-2 holding in the side of the fender. the rest are on top. if the bumper doesnt come off easily, there is still a clip attached.
 
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