SOS

So I normally keep my oil cooler fan running (with the switch mod) when I'm on the track, but now I'm wondering whether or not the spinning fan may actually be hindering air flow to the cooler when at high speed. I know it definitely helps to have the fan on during in-laps and cool down laps, but what about during hot laps? What do u guys do? Thoughts?

Quadcammer

why not do a lap with it on, and one with it off and see which one has higher oil temps?

Cupcar

FWIW, 964 Cup cars deleted the cooler, rationale was that at high speed the fan actually impedes flow even at its highest speed.

Question is: How fast does one have to go to be going faster than the fan can push air?

Once that speed is reached, the area the fan occupies does nothing but block air flow through the cooler - and it is a substantial percentage of the cooler's area.

SOS

Perhaps if I had a better aftermarket oil temp gauge then that might work, but the stock temp gauge doesn't seem like a precision instrument. Plus obviously there are so many other variables within a session that could swing a stock gauge either way.

Just thought I'd see what others do out there.

SOS

Do u mean that they deleted the cooler fan, or the cooler itself? It would be interesting to see if anyone has actually done the research to determine the crossover speed.

FrenchToast

Theoretically, I would imagine it would be whatever speed the fan pushes air at. Slower- fan is useful. Faster- fan is useless.

Take care,

e9stibi

Turn it on at the cool down lap. I just got a second oil cooler which really resolves the heat issue fort track use. I should have dine this sooner ....

Cupcar

Opps. Yes i mean fan removed only

Cupcar

The stock gauge is pretty accurate, it is really a VDO unit and uses the same sensors as VDO aftermarket, but with different threads to make it a Porsche only part.

The temp is measured at the main gallery and is the oil temp going to the main bearings so is where you want to measure it.

My bet is for track use, one is better off without the fan. One thing too is to make sure that the foam seals to the bumper cap and around the cooler are there and have not rotted away - otherwise air can go around rather than through the cooler. Also make sure the cooler is not obstructed with road trash too.

jscott82

I thought the same thing too.... I was wrong (at least with a single oil cooler)... After removing the fan and shroud, I could only go 5-10 minutes on track before temps crossed the 9:00 mark quickly heading north...

I now have two coolers and the fan reinstalled... With two coolers I don't think the fan is necessary but have it just in case I get stuck on the grid...

Cupcar

Good data. Interesting.

e9stibi

+2. Same setup that I have and I use the fan only in the cool down lap. One of the most effective mods I ever made and I should have done it earlier. If you track your 993 "regularly", do it. The GT Cooler from Carnewal.com will save you big time on the mid to long-term.

After installation for leak testing:

Cupcar

I had a 964 USA Cup and installed the factory RSR kit which placed a second radiator on the left identical to the one that is already on the right.

Even running on the street, I had no issues running no fans at all - although street time was limited.

Bill Verburg

or run a fan on the left cooler and none on the right, this works best w/o A/C