Fender Mounted Oil Cooler - How effective??

mikedsilva · 01-31-2023, 06:44 PM

I tried searching, but wasn't able to find my answer.
How much heat does the carrera style oil cooler remove compared to the stock trombone?

I read on the PP article about installing the cooler, that when Porsche upgraded from the trombone to the Brass Tube cooler, it removed approx 30 deg F (or 16 C).

Does the Carrera style finned cooler remove much more?

I recently installed a finn style cooler supplied localled here in Aus. It's quite a thick core and approx 20mm thicker than the carrera cooler. And I added a SPAL fan too.
When using an infrared thermometer to measure the inlet on the cooler versus the outlet, I see a temp drop of approx 20C / 36F.

Is this considered a reasonable method for measuring the effectiveness of the cooler?
Has any one measured similarly on a CSF cooler and compared to stock oem cooler?

ed mayo · 01-31-2023, 07:18 PM

Do you have the OE style louvered plate behind the cooler? That is what creates air flow thru the cooler.

mikedsilva · 01-31-2023, 07:22 PM

Quote:

Originally Posted by ed mayo

Do you have the OE style louvered plate behind the cooler? That is what creates air flow thru the cooler.

Do you mean the stone guard that protects the cooler from rocks potentially thrown at it by the front tyre?

If so, then yes... but the bottom half needed to be cut off, to clear the wheel on full left lock.

ed mayo · 01-31-2023, 07:42 PM

The louvered plate creates low pressure around each louver to help pull air thru from wheel rotation air flow, and the plate closes all the area around the cooler so all the air must go thru the cooler. You have lost a little of the efficiency.

mikedsilva · 01-31-2023, 08:21 PM

Would like to hear from anyone that has measured their oil temp going in and coming out of their cooler.

Bill Douglas · 01-31-2023, 08:54 PM

Mike I've never actual measured it, but out of curiosity put my hand on the out pipe and the back to pipe, and noticed a big difference. Mine is your usual Carrera cooler on a SC without a fan.

All that surface area.

And the temperature gauge indicates it's never got much above the horizontal mark including track days.

kent olsen · kent olsen's Garage

I have a large cooler in my fender, don't remember what kind, it's been there for 10-15 years.

When I used to track the car, all was well especially on a track with a long straight. But after moving from Florida to Oregon the tracks here, with the exception of Portland, didn't have a long straight. I became a little uncomfortable with the temps, soooo. I had already removed the left battery on my 72 911 and only had one in the right pocket. I got a new battery and re-located it into the smugglers box. Then I cut out the battery box and modded the area behind the cooler to only allow air to flow thru the cooler before exiting into the fender well.

This has worked very well and it doesn't take much forward speed to bring the temp down.

GH85Carrera · GH85Carrera's Garage

My 85 Carrera came with the cooler of course. No fan however.

I added a fan many years ago. It is on a toggle switch so it has full driver control for the fan comnig on.

In slow around town driving, the fan helps a lot. It even helps on the highway at 70 mph on really hot days. I did a test on a cross country drive. The oil temp settled down and stayed constant, 70 to 75 MPH on the interstate. I turned off the fan, and after 30 minutes the oil temp had climbed. I turned on the fan, and it slowly dropped over an hour. I turned it off, and and it started going up again. I just left it on all the way home.

When I added the fan, I had to remove the cooler. The old hoses were seeping, so they got replaced. Be sure to get a new seal to force the air flow through the cooler, and not around it.

If you go for a Carrera style cooler, be sure to get the fan if you drive in really hot conditions.

Bill Verburg · Bill Verburg's Garage

Quote:

Originally Posted by mikedsilva

I tried searching, but wasn't able to find my answer.
How much heat does the carrera style oil cooler remove compared to the stock trombone?

I read on the PP article about installing the cooler, that when Porsche upgraded from the trombone to the Brass Tube cooler, it removed approx 30 deg F (or 16 C).

Does the Carrera style finned cooler remove much more?

I recently installed a finn style cooler supplied localled here in Aus. It's quite a thick core and approx 20mm thicker than the carrera cooler. And I added a SPAL fan too.
When using an infrared thermometer to measure the inlet on the cooler versus the outlet, I see a temp drop of approx 20C / 36F.

Is this considered a reasonable method for measuring the effectiveness of the cooler?
Has any one measured similarly on a CSF cooler and compared to stock oem cooler?

The finned and multitube Carrera 3.2 fender coolers operate in different ways.

The finned ones use airflow, the more air flowing the better they work but w/o that flow the worse. A aux finis recommended for slow speed operation.

The multitube also use air flow but don't rely on it as much, They rely on flow + thermal mass, aux fans don't help them as much.

neither will be adequate for much higher than stock hp loads

w/o a fan the tube type will be better for low speed use and the fin type for high-speed use.