I decided to make my own oil cooler kit. After some tinkering, I ended up with a dual setup using a 25 row cooler on the passenger side and keeping the stock cooler on the driver side. Overall, I'm happy with how it turned out, and I didn't break the bank. After some hard driving tonight, I saw lower and more consistent water temps, which was my goal. The car has BNRs, AC, cat, smic, etc. and runs close to 400 whp - i.e. it can get hot.

Parts list (cost was $403):
Banzai oil cooler bracket
25 row oil cooler
Mishimoto Thermostat (+160 deg internal thermostat, you have to buy this separately)
15' 10 AN nylon braided hose
M22 X 1.5 to 10 AN adapter fitting (4x)
Straight 10 AN hose end fitting (3x)
180 deg 10 AN hose end fitting (2x)
90 deg 10 AN hose end fitting (2x)
120 deg 10 AN hose end fitting (1x)
45 deg 10 AN hose end fitting (2x)

Note that I had to remove two 3" sections of under tray sidewalls to accommodate the thermostat location. One in the side of the main under tray and the other in the side of the smaller oil cooler under tray piece. Both were minor and didn't affect the performance or dexterity of the under trays.

Overall, everything fits well and is secure.

Pics -

 

... more pics -

 

... also, if you're curious, the lines fit perfectly between the under tray and bumper.

 

Nice! I was wondering how the lines would run from one side to the other. The Sakebomb kit runs the lines through the front bumper rebar.

Do you have any ducting to the oil cooler?

Dale

 

Thanks. There are a few unique challenges to this approach over a typical aftermarket dual setup. Mainly, the oil cooler ports are inverted, one side on the top and one on the bottom, and you have to mount / connect the external thermostat so that it only controls the aftermarket cooler. I tried a lot of different options and this seemed to be best.

I don't have any ducting, but there's only about 1/4" between the bumper and the cooler.

 

Is the second thermostat necessary? I don't have a clear understanding for how the OEM duals work, but I got the impression that only the first one in the circuit needs a thermostat/bypass.

 

I'm curious what your estimated water temp reduction is? With a single stock cooler, I would normally see oil temps about 20 degrees higher than water temps.

 

The OEM duals each have a thermostat. When open, most of the oil bypasses the cooler, when closed it's all forced through the cooler. Oil is always under pressure in the cooler to maintain pressure upon thermostat closure. If the second cooler didn't have a thermostat, oil would pass through regardless, causing potentially long warm up times. Aftermarket dual kits have the thermostat prior to both coolers.

 

My car has AC, stock location radiator, a cat, and SMIC running sequential BNRs at 16 lbs. I drove it hard at full boost and lots of redlining for 20 or 30 minutes and never saw water temps above 89 deg c on an 80 evening. It's hard to say for sure but I believe it typically would have been 92 or so previously in similar driving conditions. Nothing dramatic, but it was only one drive so far.

 

OP,

 

I used the stock lines. See pic above where the rubber stock lines connect to the nylon lines. You can also run the lines as I have here, but directly to the block and/or filter housing. Just need a few more fittings. I can look those up if you'd like. I may even have them... I was originally going to go that route, but my stock lines were in good condition, and this was easier I also like how the oem filter housing hard-line is routed.

I know the SBG is a good kit, but I prefer to have the thermostat mounted to a non moving / vibrating location.

 

^ also keep in mind that this routing works because the stock DS cooler has an internal thermostat. For two aftermarket coolers, you'd need to route the TS differently.

 

Appreciated. Thanks again.

 

how did you get the AN lines attached to the factory lines?

 

I don’t remember , but from the pics it looks like I used the M22 X 1.5 to 10 AN adapter fittings. Here’s a couple more pics. The list above is the full list I used, so once your in there, it will make sense.