Droops83

No oil temp gauge yet. I hardly have time to work on my own car, and when I do I'm usually too lazy. Hence scrambling to install the 2nd stock cooler I had sitting on the shelf for ages the night before a track event . . . .

My factory oil pressure gauge is pegged at just below 5 bar hot at anything above 2,500-3,000 RPM, same as before the extra cooler. My engine has 130K miles and has never been apart.

At idle I see 3 bar warm on the street, same as before. Hot coming off track, it is now around 2 bar at idle, whereas before it would be barely above 1. Once again I'm sure most of this is due to cooler oil, but part of it could be attributed to changing oil type at the same time. I wish I could have done it in stages, but didn't have time.

Your observation about pressure drop through the system once the oil thermostat opens makes sense, but I haven't seen any difference since installing the 2nd cooler.

I wonder the same thing. My condenser wasn't TOO packed with crap, but it could have been just enough to make a difference. My coolant temps do not read any cooler in normal driving than they did before, only during hard track driving. I do believe that cooler oil can equal cooler water temps, especially since I still run the factory "wet" turbo setup w/ the auxilliary water pump. Many racers remove it since it superheats the coolant on track running through the red-hot turbo, but I like the idea of coolant running to the turbo after shutoff since this is also my only car. I would think that running cooler oil to the turbo can knock down the temp of the coolant since they are going to the same place.

Once again, I wish that I could have done it in stages and compared results. Maybe the next person who does this mod (and somehow keeps A/C) and tracks it on a hot day could monitor the results and post them.

Droops83

They are M22.

Jeff N.

Thanks for the notes Chris.

I'm seeing about 4bar hot on Mobil 1 15/50. I'm wondering if it's getting time for a bottom end rebuild. 190k, rod bearings done at 140k.

Droops83

For those who were wondering, I just looked under the '89 we have in the shop, and it uses the same condenser/hoses as the '86. In fact, according to PET, even the 968 uses the same part #s for the condenser and hoses.

So, anyone hoping to keep the factory A/C and mount an additional factory oil cooler in that location would have to space it out from the radiator frame like I did, and fill in that space and/or block it off so that no air gets between the 2. As previously mentioned, this also eliminates the need to move/modify the headlight wiring harness.

Duke

Full warmed up after some highway testing 3 bar @ idle.
Probably is a bit less at idle directly after a track session.

Ski

I'll just chime in on this, haven't been following it a lot, but we see 2.0 to 2.5 at hot idle after a track session, max oil temp seen is 220-230 but that's hot ambient and no session in between my drive or Jim's drive, ie we try to schedule the car to get a rest between white and blue sessions to cool it down; green drives between white and blue solo sessions.

Jeff N.

Bret - can you help with the following?

What are your hot, high RPM oil pressures?
What brand and weight oil are you running?
How many miles on your bottom end?
Was the last (if any) rebuild rods only or rods and mains?
Where are you measuring your oil temp?

This should help with various comparisons.

Cheers!

Jeff

Ski

disclaimer, this is from old engine, new one has not been on the track yet but everything is the same and all have been cleaned.