Most efficient oil cooler location.

[C-Gazer]

What location has proven to be the most efficient for an oil cooler in a turbo NB ? The most popular appears to be the cooler bolted to the steering rack (Flying Miata) while some have opted for mounting the oil cooler in the front well immediately behind the fog light opening. I had considered ducting the cooler on the steering rack through the splash tray. Has anyone managed to locate the oil cooler in the intercooler, a/c condenser and radiator area with good results ?

[Nevyn72]

Well the most efficient is the PWR combined Radiator/cooler but it's not cheap! ~$1200.



Then you need to add slimline fans to make it fit as it's quite thick too.....

Any other solution requires quite a bit of surgery but I think Lokiel's solution of mounting behind the driver's fog light with shrouding is the most elegant.

If you haven't replaced the radiator already then by the time you add together the cost of a 'good' aftermarket radiator plus the oil cooler kit and mounting hardware you're not that far short of the cost of the PWR twin-cooler anyway and you get to keep the fog lights!

[Lokiel]

I'll 2nd the PWR combined Radiator/cooler, especially if you need to replace the radiator anyway - it's not simply a drop-in replacement though, apparently it needs some "massaging" to fit as well as slimline fans.

My DIY behind-the-foglight solution ended up being quite expensive since it was a custom job and I ended up buying LOTS of fittings and extra hose that I didn't end up using. It does work well though. Note that you should use AN-10 hoses/fittings where possible, anything smaller will limit the flow required to optimise your cooling on a turbocharged application.

The PWR combined Radiator/cooler places the oil barbs in a very convenient location; my oil cooler hoses need to loop from the wheel arch back up into the engine bay to the oil filter relocation block/thermostat so the hoses are longer than I'd like.

Add an oil drain plug to the PWR combined Radiator/cooler and it would be my choice IF you think you need a replacement radiator anyway.

[deviant]

Putting the oil cooler in the 'stack' of intercooler / radiator / AC heat exchanger is a no go, it limits air flow far to much.

Mine is behind the fog light opening but I'm not that happy with it. Not nearly enough airflow over it.

[NitroDann]

The steering rack mount is far from ideal, FM chooses it because its the only location 100% common to all models.

Dann

[Patrick Bramston]

front bumper works on NA,s, sits on the reinforcing.

[Magpie]

I'll second/third/fourth the PWR combo, hey I have one http://mx5cartalk.com/forum/viewtopic.php?p=698639#p698639

Whatever choice you make ensure that it gets air ducted in, the shroud should not allow any air to go anywhere but through the oil cooler and to duct the air away.

One thing to consider if doing the PWR is to have an oil temp sensor point added.

[Lokiel]

Putting the oil cooler in the 'stack' of intercooler / radiator / AC heat exchanger is a no go, it limits air flow far to much.

Mine is behind the fog light opening but I'm not that happy with it. Not nearly enough airflow over it.

Have you ducted it at all? Ducting ensures that you'll get the maximum air through it rather than simply flowing around it:

[bruce]

Just thinking out aloud. Don't auto transmission radiators have an auto trans line running to them for a bit of cooling? Wonder if you could make use of that (whether it would be enough cooling though).

[Okibi]

...you need to add slimline fans to make it fit as it's quite thick too....

I didn't need to on the standard NB (just cut them as per the picture) but it might have issues fitting on my SE, I haven't tried yet.

[Si.G]

erm - not sure about the cooler being in front of the wheel. The Lancer Evo 7 group N rally cars had that arrangement - was not very reliable, would need to be pretty well guarded in a way that does not stop air flow. I know our cars are not for rally, but you only need a stone to hit it hard enough, bye bye oil and hello slippy front tyre

On the PWR rad - a friend runs one on his supercharge NA8, but still sees water temps of over 100deg C on the track. Interesting thing is, my car runs with a 'middle' priced rad (ebay ), a 13 row mocal oil cooler in front of the steering rack (no under tray) and it runs at about 88-90 on the track. On a cold day, I struggle to get the water temp above 70 on the freeway. fyi - the engine has a thermostat in, so I would guess the cooling is from the oil cooler, which as no thermostatic switch in. I have not ducted the oil cooler yet, but the rad and intercooler are fully boxed in, with the intercooler having its own ducting that directs some air over the top to the rad.

my verdict is, steering rack mount works

[C-Gazer]

Just thinking out aloud. Don't auto transmission radiators have an auto trans line running to them for a bit of cooling? Wonder if you could make use of that (whether it would be enough cooling though).

Great idea. Has anyone used an auto transmission radiator and run the engine oil through the cooler. The question comes to mind can the oil cooler in the auto transmission radiator take engine oil pressure?

[sailaholic]

I've got an auto radiator but have never tried it. I would think the bigger issue would be are the lines in the radiator big enough for the amount of oil flow required?

I would assume this is why the factory used the water cooled heat exchanger on the block rather then pipe it to the radiator.