5mt oil cooler

[Canadian818]

I know this has been discussed, but I believe most of the info is lost in build threads that I can’t find. I’d imagine any oil cooler will work, but what are we looking for in a pump? Cx Racing has a 3.7gpm pump for fairly cheap, summit has Tilton pumps for a little more rated at 1-2gpm. Should we use a filter before the pump?

If anyone has info in their build thread, or knows where I’ve seen some of this on here before please post a link.

[Hobby Racer]

3.7 gpm is way too much, around 1 gpm is good. Use a filter before the pump.

I use a 3.7 gpm cheap e-bay pump but I slow it down to around 1 gpm.
Information about my 5MT trans cooler starts here:

https://thefactoryfiveforum.com/showthread.php?23199-John-s-EZ36R-H6-818R-Build&p=313246&viewfull=1#post313246

And ends here with a few posts about the trans cooler in between.

https://thefactoryfiveforum.com/showthread.php?23199-John-s-EZ36R-H6-818R-Build&p=315148&viewfull=1#post315148

[Canadian818]

Thanks Hobby Racer, I knew it was someone posting regularly this winter that did it. Are you still pumping the oil back into the rear cover? Have you considered checking the fluid level with the pump on so as to ensure it stays high enough for the gears to pick it up?

[Hobby Racer]

Still pumping it back in the rear. I have not tried checking the level with the pump running.

[Sgt.Gator]

Good timing on bringing this up. I just pulled out my old 5MT cooler stuff to sell the tranny to one of the other racers here.

My Legacy GT race car was built originally by the Subaru Road Race Team (Joe Aquilante at Phoenix Performance) in 2005 and raced in the Grand Am Cup in 2006. When I bought it from Joe it came with the following tranny cooler setup:
1) Legacy GT 5 speed. The LGT 5 speed has the advantage of not having a speedometer gear so the speedometer gear hole is available to route the oil back into the tranny.
2) Welded steel AN fittings in drilled out Subaru oem plugs in the drain and speedo ports. See pics.
3) Weldon 9200 A pump.
4) All -8AN lines and fittings.
5) Mocal cooler w/ Spal fan.
6) Identical setup for the rear diff, obviously not applicable for an 818.
7) Switches on dash to control the pumps and the fans.
8) Tees with temp sensors logged and displayed thru the AIM dash.
9) Inline filters.
This is expensive stuff...$475 for each pump in 2018 $$$.
Most of the pump manufacturers will tell you to put the cooler before the pump (the pump is working with cooler oil and lasts longer). However this system was setup with the coolers after the pumps. That cools the heat from both the engine and the pump before it goes back in the tranny.
Hope this helps.

Fittings:

https://uyqcnw.by.files.1drv.com/y4mga6ndph5kNp6ujxPFAuYOqRKc3L3o8kgByi7_66P6IcRmc3 jSZ609KP1z9MrRWQMa-hn7nfkV5Foo_vGM0kCaxrdwOZBlt09sWxk7g7l4mpWyD5iysp7 LOrNAcrPngL2DR0p2wTfcF_Y_nEC87yU9LW1dyQTeUsiG3AQ1x d6o0ThJ2966Sox6zxwqHHPgDsTq7uMUKLOKotMKz9U1ln_pQ?w idth=576&height=327&cropmode=none

Drain:

https://viqcnw.by.files.1drv.com/y4m_I4prmtUC9v9tUGcLSVu3Qkl57bZ9VtO1yhhEwQOkCUaDML 6xz69uLm8FWwomzxHYiTM3mytAo5OLAz5U_Afq0pyly_T0XlR_ LNR-o0z28d-cuduP8E9S5ChqjNTG8q_loQxnKesXgbPGdLqUYn2SZr9b-s5sidk4kitvUi02aCy-tdh9V3x1k5_-Pum8WWNisd7JzXYvPMZpOJKSo5AFw?width=720&height=348&cropmode=none

Fill in the Speedo port:

https://u4qcnw.by.files.1drv.com/y4mLtXzeoTya3Rv88lgrRQOppkLyfEyFjJgPVK_tScqg6y_AGk 5dWT7KrJpNm5tapWLOiUYyFWCm0ZJMTNyFVvmbtJtpMxhY4sPM rSvC6u5Uq3f2c2h8zBKxCWWF7caTI1WYDokZG5UfLJMmC9ROIG 6HoFrXTW0AbvoHlS_PwGq6NywZzSjXb7iuqEbD8a96lrJf9bgU TwV2MkpyTIhTyYdiA?width=719&height=460&cropmode=none

[Canadian818]

Nice setup Gator, and thanks for adding it here for future reference.

Any thought on ideal temps? I’m looking to use an inline temp sensor and make the system self contained. These are the parts I’m thinking of using.

Temp sensor (https://www.summitracing.com/parts/der-35021) on at 180* off at 165*
Pump (https://www.summitracing.com/parts/til-40-524) 1-2 gph
Inline filter (https://www.summitracing.com/parts/vpe-16738)
Cooler (https://www.summitracing.com/parts/der-51610)

I’ve tapped the center diff housing on top, all the way forward, just to the divers side of the center rib. So that’ll put the cooled oil right on top of 5th gear.

[C.Plavan]

Still pumping it back in the rear. I have not tried checking the level with the pump running.

You really should check. I have a setup on my Porsche 911 racer. I fill the trans fluid to normal level with pump off, then click on pump then top off to correct level with pump flowing. You will be amazed on the amount of gear oil you should add because of the oil displacement.

[C.Plavan]

Nice setup Gator, and thanks for adding it here for future reference.

Any thought on ideal temps? I’m looking to use an inline temp sensor and make the system self contained. These are the parts I’m thinking of using.

Temp sensor (https://www.summitracing.com/parts/der-35021) on at 180* off at 165*
Pump (https://www.summitracing.com/parts/til-40-524) 1-2 gph
Inline filter (https://www.summitracing.com/parts/vpe-16738)
Cooler (https://www.summitracing.com/parts/der-51610)

I’ve tapped the center diff housing on top, all the way forward, just to the divers side of the center rib. So that’ll put the cooled oil right on top of 5th gear.

I have found that most cars with a transaxle, the oil of the gearbox and motor will mirror each other once adding a trans cooler. www.improvedracing.com has some trick inline switches and stuff you can adapt. I think that setup you outlined will be perfect.

[Sgt.Gator]

Nice setup Gator, and thanks for adding it here for future reference.

Any thought on ideal temps? I’m looking to use an inline temp sensor and make the system self contained. These are the parts I’m thinking of using.

Temp sensor (https://www.summitracing.com/parts/der-35021) on at 180* off at 165*
Pump (https://www.summitracing.com/parts/til-40-524) 1-2 gph
Inline filter (https://www.summitracing.com/parts/vpe-16738)
Cooler (https://www.summitracing.com/parts/der-51610)

I’ve tapped the center diff housing on top, all the way forward, just to the divers side of the center rib. So that’ll put the cooled oil right on top of 5th gear.

That list is very good with two notes.
I use the the same Derale temp sensor on my STI oil cooler, it works great. However you can't or at least shouldn't run the full amperage of the pump draw thru it. Use a relay to take the switch signal and then let the relay switch the pump.

I have that little filter too but I was only going to use it for my turbo feed line, and it will be in a very accessible place. The problem with the little filters is they are a simple screen. That's fine unless you forget to check it (all the time). On my race cars it will be on the daily post event check list. The reason is that screen can fill up very quickly and block the oil. For the tranny you might want to use a much larger filter that you don't need to check every day. On the plus size if it does block up it will just stop the flow and you'll see tranny temps starting to rise. Probably not catastrophic like blocked flow to the turbo bearing. On the LGT I used one of the 5-6" long ones that have fairly large filters. I was just looking at these filters listed in the PRI industry magazine because I'd like more filter media than the little screen provides. : https://motorsports.flowezyfilters.com The prices are very reasonable for a Made in the USA product.

[Hobby Racer]

You really should check. I have a setup on my Porsche 911 racer. I fill the trans fluid to normal level with pump off, then click on pump then top off to correct level with pump flowing. You will be amazed on the amount of gear oil you should add because of the oil displacement.

Wow, checked this today. With the pump running I need to add another 1.5 - 2.0 quarts to obtain normal level. So now the level is correct when the pump is on but what about when its off? Will the extra gear oil cause an issue when running cold without the pump?

[Canadian818]

Thanks Chad for adding!

Gator, I hear what your saying about the filter. The ones you listed seem pretty sweet but it got me thinking, why not use a remote oil filter base and use a engine oil filter?

Hobby, I too was wondering about that. I think that a little drag on the gears would be probably unnoticeable however I think I’m going to vent the rear cover with a hose looped high and back down pointing to the ground by the diffuser. My concern being that if the case somehow got pressurized I don’t want the dipstick blowing out and oil hitting my exhaust.

[C.Plavan]

Wow, checked this today. With the pump running I need to add another 1.5 - 2.0 quarts to obtain normal level. So now the level is correct when the pump is on but what about when its off? Will the extra gear oil cause an issue when running cold without the pump?

Not sure on the Suby-but I doubt anything bad will happen. You could always add a one way check valve, Or vent like Adam is thinking.

Nothing bad has happened on the Porsche at all when I forget to turn the pump on (The transmission does have a vent on top). I usally turn it on towards the end of the pace lap once warmed up for the first run/race of the day.

[Sgt.Gator]

Canadian you could use a remote engine oil filter. You'd have to mount it on the pressure side of the pump otw to the cooler > trans. You wouldn't want to try to suck the oil thru the filter. Inline filters are typically used because of the space constraint under a car near the transmission, and in fuel lines for the same reason.

[Canadian818]

Canadian you could use a remote engine oil filter. You'd have to mount it on the pressure side of the pump otw to the cooler > trans. You wouldn't want to try to suck the oil thru the filter. Inline filters are typically used because of the space constraint under a car near the transmission, and in fuel lines for the same reason.

So it’s ok to suck oil through an inline filter? Don’t like the idea of putting the filter after the pump.

[C.Plavan]

So it’s ok to suck oil through an inline filter? Don’t like the idea of putting the filter after the pump.

I have an inline filter before the pump- I myself would not have a filter after the pump. (Genesis pump) http://www.hrpworld.com/store/default/genesis-technologies-lube-pump-vilton-seals-gen-gc1111.html

https://i.imgur.com/Q7reCOxl.jpg

The pump sprays the R&P and sucks out the bottom drain hole, then through inline filter. I blew 2nd gear at COTA (48 year old gear...lol) and the filter caught all the pieces before ruining the $200 pump and $180 cooler.

[Sgt.Gator]

So it’s ok to suck oil through an inline filter? Don’t like the idea of putting the filter after the pump.

Yes, like what Chad did. Of course the filter media size and micron sizing matters too. Be sure to check the micron size when you get the filter, I have an Earls inline filter I got at Summit. It says 140 micron, but that's BS, I swear if you used it as window screen your house would be full of mosquitoes! Beach sand pours thru it. https://www.summitracing.com/parts/ear-230308erl/overview/

If you're sucking the oil thru it I wouldn't go too fine on the micron size.

Looking at Chad's Moroso at Summit, it says it has a 16 mesh filter, which equates to 1190 microns. That's really large for an oil filter screen, which is why he can suck the oil thru it. Grains of table salt are 100 microns, and window screen is 1,400 microns. But we're not worried about main crankshaft bearings here, just passing thru the pump and cooler without damaging them. For that purpose it works great. But it's not going to clean your transmission oil like a engine oil filter does. The fine screen inline filters or a remote mount engine oil filter would have to be on the pressure side of the pump to catch that stuff.

I don't have one on my STI cooler because it's using the internal OEM pump, and has one of those magnetic drain plugs that collects metal shavings. I suppose I could put a filter on the cooler line but I don't know if the internal pump has the power to push the oil thru the lines, cooler, and filter. It wasn't designed for that application so I'm not going to risk it.

The nice thing about FlowEzy is you can call them and discuss what you are doing to get their recommendation.

[Canadian818]

This is where I installed my oil return. I also tapped a hole for a vent line.

http://i1113.photobucket.com/albums/k519/pope83/88B2C797-0638-481B-82F9-68996A1241A0_1.jpg (http://s1113.photobucket.com/user/pope83/media/88B2C797-0638-481B-82F9-68996A1241A0_1.jpg.html)