Texas vs. the Targa: Advice Needed on Oil Coolers

universeman · universeman's Garage

Well, a month ago I was here crying about rainwater leaks.

Now I'm trying to save my 911 from Texas' legendary summer heat. Seems she was equipped with a trombone oil cooler to cool the engine, which to paraphrase what we say in Texas, is like taking a trombone to a gunfight.

Today in stop and go traffic on IH-35 between San Antonio and Austin, I got above the second white mark (248?) for a little while. Not good.

At 70mph, it was running just below that second white mark. Seems too hot.

Is the Carrera cooler the only way to go, or have ppl had luck with Mocal or ER coolers also? Just looking for some advice from someone in a Texas-like (i.e. surface-of-the-sun hot) climate!

Thanks!

IROC · IROC's Garage

I ran the Mocal kit on both a 2.7 and a 3.2 and it worked fine for street use. It was not enough to keep the 3.2 cool on the track, though. If your planned usage is mainly street, the Mocal would be sufficient.

jpnovak · 06-06-2015, 03:47 PM

Dual radiator-style fender oil coolers or a front mount. No other way here if you want to drive June to Sept.

Do also make sure the fan is working.

JOHN21BLACK · JOHN21BLACK's Garage

My car will not go above 190 since I installed front 9 row cooler with 16AN lines. I live in Los Angeles and the 5 freeway sucks 24/7

Jack Stands · Jack Stands's Garage

If you want to run stock bumpers and valences, the Carrera, Mocal, or Turbotrol (if you can find a good used one) cooler would be the best choices. The trombone coolers really didn't do too much other than provide a path for the oil to return back to the engine. The oil lines along the longs probably do as much cooling as the actual trombone.

fanaudical · fanaudical's Garage

I've got the Mocal on my 2.7 and finally got to test it today in 90F heat (first time I've driven the car in this kind of heat since I've gotten it together). Temp got to ~195F max.

74-911 · 07:33 PM

I've been using the Turbotrol for years in the 2.7L (originally had no external oil cooler - definitely not good!!). This mainly in the San Antonio, Corpus, Houston areas where it gets plenty hot.

PooShee · PooShee's Garage

A/c delete and remove the components under the deck lid grill...
I live on the surface of the sun as well and it stays pretty cool despite all that

Stop and go traffic is no beuno for you and passengers though

s2per · s2per's Garage

Mocal upgrade in a stock-valanced car is a good way to go, even with a/c. But be sure all of your factory lines are crimp-free. Ask me how I know.

IROC · IROC's Garage

It should also be noted that a fan with the Mocal unit is a must. With the fan on, my 3.2 never got over 185F or so in Alabama summers.

06-07-2015, 05:07 AM

Make sure your oil temp sender is working correctly. Check this thread out.

Overheating SC

12:18 PM

Another thread on overheating with some things to look at.

Need serious help now, what's left, JW, Warren, Wayne?

mreid · 06-07-2015, 06:56 AM

I have a 3.6 in my 1974 with only the front valance oil cooler. It stays below 200 even in the Texas August heat where I overheat. The secret is air flow. You must provide a path for air flow or a fan.

universeman · universeman's Garage

Thanks all! A few other things to note: I tried turning off the A/C - no change to oil temperature. I also turned the heat on, meaning the blower fan in the engine compartment. Still no change. Ran both log enough at constant ground speed to be "scientific." Appears that use of either one does not impact engine temp. However I can see how an A/C delete would potentially make a change to the amount of airflow through the deck lid.

Sent from my iPhone using Tapatalk

mreid · 06-07-2015, 08:18 AM

Yeah, and then the driver would overheat. For what it's worth, I have three Porsches and none of them have a/c. I just don't drive them in the hot afternoon.

How did you get your a/c to work in an SC?

Reiver · 06-07-2015, 09:44 AM

I've a euro SC with 9.8/1 comp and drive year round in AZ...often in 100-110 degrees.
I put a stock later Carrera oil cooler and block off/fan in place of the trombone.
I rarely see 210 degrees running at 75 mph for long periods of time...usually 200. .. 210 when flogging it a bit.
The fan (switched on the dash) will lower temps 10-15 degrees on call. Yesterday at 95 ambient was running 190-195.
Bought the cooler/block off fan used and it was a DIY....works perfectly and fits perfectly as Porsche designed it.

Morrie · 06-07-2015, 11:56 AM

Just as a data point, I have a 76 911S running a 1982 SC motor. I have a carrera cooler up front with a cooling fan, and have AC in the car. With the cooling fan running in 90 degree heat here, I am able to keep the AC runnning when stopped in traffic (not that it works all that great, but lets not go there in this thread).
Another rat hole we probably don't want to go down is oil weight. I am running Valvoline VR1 20W50 here....

Anyway, just a single successful data point.

Cheers,
Morrie

RSTarga · 06-07-2015, 11:57 AM

I have a 73 Targa with a 2.7 MFI, with a/c and use the 28 tube early carrera cooler. Never see above 210 in San Antonio with a/c on.
Probably your best and easiest solution is a late carrera radiator type cooler with a fan.
I started with the trombone then the Turbotrol, then an aftermarket radiator with no fan, finally the 28 Tube cooler as the newer radiator with fan had not come out.

universeman · universeman's Garage

My A/C actually does an OK job (it's stock) if you full blast it and you're moving. I'll probably be "reversing the gases" on it at some point also

Does anyone run the bumper scoop and think it does any good?

RSTarga · 06-07-2015, 12:09 PM

I have my front condenser standing up in an RS front spoiler along with the over engine condensor and have excellent a/c on the move, merely good in stop and go traffic.
If you are talking about the scoop to the oil cooler with no fan, I think the fan is preferable.Make sure the fairing and vents around and behind the radiator are in place.