914-6 2.7 runs hot, need oil cooler advice for non-front application

[jwinner11]

My 914-6 2.7 runs a little hot (230-240 degrees) so I am looking for advice on adding an external oil cooler. Thinking of adding a Mocal/Setrab external cooler to the underside of the rear trunk, has anybody used this option and if so did it help? Please let me know if you have any other ideas. I am not plumbed for a GT style front cooler which is why I am not pursuing that $$$ option. Thank you, James.

[tailwind22]

Here is a pic of my double fan Setrab mounted on the underside of the truck cooling my 2270 Raby 4 cylinder.

[Dave at Pelican Parts]

I have also used it, and it did help some. It is not optimal in a number of ways--and most of those are in the "cool air flow" arena. This lives in a warm area with relatively little air flow. You'll need a fan for it to be more than an extra oil reservoir, and even then it wont be as effective as it could be.

Oil coolers work best when you can get clean, cool, high-pressure air to them, force that air to go through the cooler, and then get it to leave as quickly as possible. The front-trunk mounted cooler is about as good as you can get with a 914, because the nose of the car is generally where the cleanest and coolest area of high pressure air is.

That said, the setup above can be good enough! It also generally involves a lot less cutting of the body than making provisions for the front-mounted cooler. It also leaves your interior room uncompromised (most oil-line routing goes through at least a little of the passenger compartment, plus you lose a good amount of front trunk space to the cooler ducting) and is relatively stealthy.

Those are the reasons I went with the above setup.

--DD

[zedsn]

Can you run a passenger side front inner fender oil cooler like the 911 guys use? I had one with a thermostat controlled fan and it worked very well on my 77 911.

[GregAmy]

I installed Tangerine Racing's setup for my 4-banger; it tends to run hot in July/August. You won't want the whole setup for your /6, of course, but components of this may work for you.

http://www.tangerineracing.com/remotecooler.htm

[BoxsterGT]

If you choose to run a rear mounted Setrab Oil Cooler w/ a fan, they have 22mm fittings that accept adapters for Factory Oil Hoses or Banjo Bolts for Factory Oil Hoses.

I have M22 Banjos that are designed to crimp to Factory Oil Hoses, either 26mm (914-6 original) or 30mm (911 Late model 72>89).....



and can make up Factory Level Custom Oil Lines/Hoses to fit your Rear mounted Cooler needs.

Len.Cummings at verizon.net

[db9146]

How clean is the engine mounted oil cooler? Have you pulled it to check for any sort of oil / crud build-up?

What about the engine timing?

[Emo993]

James, any chance you have a earlier engine cooling shroud that does not have the extra oil cooler duct. And as db9146 said, clean cooler. Best, Mark

[BoxsterGT]

As db says, ignition timing make a huge difference in operating temps.

Len

[jwinner11]

Here is my shroud, definitely has the oil cooler duct. Going to install and external Setrab cooler under the rear trunk then have the ignition timing checked. Hopefully that fixes the oil temp issue.

[BoxsterGT]

Watching with interest.

Len

[Porsche 2]

Running high air/fuel mixture (>14) will also cause a hot engine.

[jwinner11]

Thank you for your reply. This engine sat for several years prior to being installed in my 914. What is the best way to check the air/fuel mixture? When you say >14, what does that value correspond to?

[Porsche 2]

You need to measure your Air/Fuel ratio in your exhaust stream with an O2 sensor with meter. If you are running carbs best is an O2 sensor on both sides of your 911 exhaust system to tune your carbs. Air/fuel (A/F) mixture can vary from very rich at or below approximately 10 to very lean 15 and above. Perfect is 14.7. There are tail pipe sensors ("stingers") at most car repair shops which test your emissions and can measure your A/F ratio. Some experts suggest A/F's with carbs should be between 13 and 14.

[767driver]

If you are running heat exchangers make sure the 2 ducts coming off the fan are connected to your to your heat exchangers. A heat exchanger with no air going through it is just a heat sink. And make sure all your engine tins are in place and sealed properly. I added an under-trunk oil cooler parallel to the trunk floor with a fan underneath the cooler pulling air downward through it. It helps a lot and with the fan running it WILL cool down when you slow down from whatever driving got it hot.

[TRE Cup]

FWIW- the engine lid should be modified ala GT with full screen. You can check oil temps back to back test by driving it first with your existing lid, then removing it and driving it again to verify the drop in oil temp. You might see about 10-15 degrees difference
Next- a couple people tried putting in a multi tube brass 911 radiant cooler in the rear wheel well> pointless exercise. Same would apply to a radiator cooler there too (unless a fan can be fitted on the radiator style) + not likely as it is really tight space in front of the right rear wheel
Next:You don't have to run oil lines thru the interior. The passenger side rocker panel gets removed to access the body parts there. There is a box section near the front wheel that will need to be pierced to pass a pair of -12 an hose passing through. The hoses go up and into the body to run back below the gas tank on the passenger side. Punch an opening in the vertical trunk to gas tank wall, attach an inline thermostat (summit or BAT ltd) and then to a 914 GT shroud housing the cooler. CSF makes a great strong cooler that can be mounted there. Punch out the impression holes on the front trunk panel and make a rectangular opening in the trunk floor to exit the heater air
Don't worry about front end lift from air under the car. If i can do 150+ in my 6 with this set up, then you won't have a problem either
As Dave at PP outlined above- fresh cool air coming in from the front is the best option