When do I need a front mount oil cooler?

[911pcars]

Originally Posted by Focker

Is there really oil coolers for water cooled v. air cooled? Other than the CSF and Setrab, I haven't seen any coolers with -12 lines.

I don't want to sound argumentative especially when I'm asking advice, but given that immediately after the fitting, the cooler chokes down to the diameter of the cooling tubes, is the difference between -10AN and -12AN that significant?

Earl's, Fluidyne and perhaps other coolers are also offered in -12AN inlet/outlet sizes. Most oil coolers (with small inlet/outlet ports) are designed for use with water-cooled engines.

As you can see from Trackrash's comparison photos, the factory fore-aft lines (ID) are about the same as -16AN hose/fittings. -12AN is the minimum size to limit system pressure drop. Luckily, most of the factory hard lines have smooth interior walls.

Compare with a -10mm AN hose/fitting dimensions:


BTW, here's a good article on choosing and installing oil coolers:
https://www.pegasusautoracing.com/document.asp?DocID=TECH00133

Sherwood

[Focker]

Thanks for all the advice guys. I think I better understand the requirements now.

[Walt Fricke]

I like the Mazda oil coolers, largely because of their cost/performance ratio. They've kept my SC race car's oil where it needs to be for years now. My approach has been to drill holes in the end tank after closing the stock openings, and have AN-12 fittings welded in. But Gordon's approach has me thinking if ever I need to do this again: He used the thermostat hole for one of the fittings, turning the cooler "upside down" from how I have, for some reason (location of bits and pieces to mount the cooler)have done it. If you can screw a standard fitting in there, that much less to pay the tig welder.

His design solves one of the problems with a cooler in this location - routing the lines so they don't bump into parts of your aftermarket IROC or similar style front valance (or full fiberglass bumper). Coming out the top looks to give you more room, at least in the picture with the bumper removed.
I guess it wouldn't work for me in my SC with its comforting aluminum bumper in place, though.



I've always used -12 hose and fittings, as it is just a little bit smaller ID than the Porsche tubes/fittings. Were I to do it again, I guess I'd consider the extra cost and (for routing purposes) OD of the -16. But -12 works. Dash-10 not really a good idea.

[BoxsterGT]

I have M30 Alum Weld Bungs that can be used for the RX-7 coolers if needed....






Threads are hard anodized and are $25ea. I also make up custom Metric Oil Lines for the early Porsche models.




For info please email me.

Len.Cummings at verizon.net

[BoxsterGT]

Thought I would bring this back, as I have had inquiries for coolers in longhood 911's, and the one shown above will clear a 73 RS type bumper and fits as factory.

Len.Cummings at verizon.net

[Gianni at Pelican Parts]

We sell a couple great cooling options from CSF Performance Coolers if you're going to an IROC bumper they have a single and dual pass front mount cooler or if you want to go the fender cooler route they just recently released an upgraded fender cooler as well.

['78 SC]

One data point:

I tracked my 1978 911SC (JE 9.5 CR, 964 cam, SSI, 2in-1out, 180 RWHP) in the summer in Texas with an Elephant Racing wide mouth cooler (plus stock on-engine cooler) with no problems. Air was ducted to the cooler through an opening in the valence (no fan). I never had temps go beyond 210F, typically lower.

[colingreene]

Please do not use Mishimoto they are made in china garbage that frequently have to be replaced.

[911 SLANT]

I used the Mazda cooler. Changed the fittings to 16AN

[sundevil64]

I am running two front oil coolers on my 930. One is a Carrera and the other is a 28 tube cooler. It's what I had and one tends to cool better when moving slower (28 tube) and the Carrera has better cooling capacity due to the fins (no fan).

Obviously you don't want to run too much cooling or you can oil mayonnaise (I hear). Has anyone run a thermostat (Mocal) between the 1st and second cooler?

This came as a thought when I was running a 930S front cooler along with the Carrera cooler.

[lvporschepilot]

I’m running a 44 row Setrab fender-well cooler with a large and super strong fan. Also have a duct cut in the front valance for more flow. Here in the Atlanta area, when pushing things during summer, even with the fan going I see 230F+. The fan does cool things when I’m off it but once it’s heat soaked it doesn’t go under 200-210F. Engine is pretty hot, twin plug 10.5:1 2.8L with DC65 camshaft and PMO 46 carbs, headers etc, somewhere around 260-275bhp. I wanted this car to retain the early Carrera look but in hindsight it probably does need a front cooler. The SC/RS front valance would be what I would run with the chonkiest huge front cooler there is. 8000rpm gets things hot

[911pcars]

If you don't already have one, install the factory oil thermostat (or equivalent) in the supply line from the engine. If you haven't looked, they're usually in front of the RR tire.

Part #7


Sherwood

[Walt Fricke]

John - it doesn't really make any sense to run a second oil thermostat anywhere, including between cooler 1 and cooler 2. More plumbing for no benefit I can see, as the factory thermostat will be closed until the engine reaches operating temperature (about 190*F). Of course, it never completely close - some oil always flows forward. Then it opens. The thermostat doesn't operate like some kind of laboratory system, where something must be kept within rigid limits at all times. So you should get the same temperature regulation regardless of how many coolers you plumb into the system.

And the engine mounted cooler has its own thermostat.

[sundevil64]

Thanks Walt for the response.

[safe]

You can always go bananas and duct it through the hood!
Keeps the oil from a 3.6 (no internal cooler) at a constant 220 even at hard extended work.
Last weekend I did a 1.5h stint, only ~75ish ambient but still. Maybe peaked at 225.

[Walt Fricke]

Magnus - doesn't this through hood outlet for front center coolers mean you can't have a spare tire up front?

I like this setup for cooling, and in my car which races with very few rules on body modifications I did just that. Two 964 coolers mounted side by side and plumbed in parallel and exiting out a sort of NACA duct shape in the hood are all the cooling my 2.8 needs, so the engine mounted cooler is converted to an oil filter.




But I can't do that on my SC race car - rules I run under don't allow it. But there is adequate room for the hot air to vent backward if you mount the cooler as far forward as you can in the valance's cutout. True, it can go under the car, affecting aero. But my class has rules which limit aero modifications anyway. And a street car's owner ought not to worry much about aero at sensible highway speeds, as long as it isn't way out of balance.

[ian c2]

Originally Posted by Walt Fricke

True, it can go under the car, affecting aero.

Underneath the car is exactly where you want it to go .
The early 70s style rsr bodywork mod behind the cooler got the rough shape ok(just needs smoothing ) , add some channeling underneath and then a rear shape to add diffusing would need to be added .
The rear is the real problem due to the lump of engine being back there …

[winders]

Originally Posted by ian c2

Underneath the car is exactly where you want it to go .

No! Underneath the car is exactly where you don't want the air to go! The best place for the air to go is out of the hood near the front of the car and over the bodywork.

The last place you want the air to go is under the car. It is better to have it go into the frunk than under the car....

[ian c2]

Yeah right .
Inverted wing Scott .
Inverted wing …..

[Walt Fricke]

This should get interesting.

Don't lots of race cars - NASCAR, for instance, as well as Porsche factor race cars - run front spoilers which are almost on the ground? To keep air out of that space, because they want a low pressure under the front, and a higher pressure above it?

A typical Porsche silhouette is a sort of a non-inverted (i.e., regular) wing shape, isn't it?