911ish oil cooler for a 914-6? Options

[Mark Henry]

I'll just keep my under rear trunk location, but always good to see/hear more ideas.

I posted this set-up done by Henry Schmidt a while back.
(IMG:http://www.914world.com/bbs2/uploads_offsite/forums.pelicanparts.com-26-1292010763.1.jpg)
(IMG:http://www.914world.com/bbs2/uploads_offsite/forums.pelicanparts.com-26-1292010763.2.jpg)

[tradisrad]

I'll just keep my under rear trunk location, but always good to see/hear more ideas.

I posted this set-up done by Henry Schmidt a while back.
(IMG:http://www.914world.com/bbs2/uploads_offsite/forums.pelicanparts.com-26-1292010763.1.jpg)
(IMG:http://www.914world.com/bbs2/uploads_offsite/forums.pelicanparts.com-26-1292010763.2.jpg)

This is what High Performance House does for his oil coolers. But, I always wondered about sucking the hot air in from the cooler; is that a problem?

[SirAndy]

This is what High Performance House does for his oil coolers. But, I always wondered about sucking the hot air in from the cooler; is that a problem?

There is a whole thread about that particular car above going through all the pros and cons and more.

I don't think we have to re-hash 20 pages of that again, do we? (IMG:style_emoticons/default/shades.gif)

[SirAndy]

And yes, the search works just fine ...

"+Henry +Schmidt"

http://www.914world.com/bbs2/index.php?sho...=Henry++Schmidt

And from the looks of it, you posted the exact same reply in that thread just two months ago ...

FWIW High Performance House likes to install the aux oil coolers on the engine lid.

(IMG:style_emoticons/default/popcorn[1].gif)

[tradisrad]

And yes, the search works just fine ...

"+Henry +Schmidt"

http://www.914world.com/bbs2/index.php?sho...=Henry++Schmidt

And from the looks of it, you posted the exact same reply in that thread just two months ago ...

FWIW High Performance House likes to install the aux oil coolers on the engine lid.

(IMG:style_emoticons/default/popcorn[1].gif)

oops...

[Mark Henry]

And yes, the search works just fine ...

Never seems to work that great for me, (IMG:style_emoticons/default/confused24.gif) often find things faster here by doing a google search.

[sww914]

I tried it, it didn't work as well (on a racecar often in the desert) as I expected. I didn't have the engine mounted oil cooler. I installed a ducted F cooler and it never got past the middle of the gauge again.

[Eric_Shea]

thermoswitch controlled fan...

Only later models. I have a "Jail bar" cooler in my 911. No fan.

[john rogers]

A couple of things to consider, all the vintage race cars I remember racing against had the external cooler in the front trunk with ducting so the hot air can come out underneath. I have seen a couple of 4 cylinder cars try coolers elseware but that never lasted. For street or auto-x use it is another matter entirely where you need to worry more about protecting the cooler from stones and all the junk that comes up from the roadway.

The biggest reason that the front fender idea won't work on a 914 is that the air coming off the tire is actually going forward fast enough due to the small space under there that no air can get in. Nearly the same happens in the rear and to prove the point, squirt some of that expanding foam stuff in there and take a good hard drive and then look to see what the heck is stuffed in the foam. You'll be shocked.

[0396]

The 911 has a much more open area behind the front headlight than the 914 does, and so I believe there is more airflow. On mine, I seem to remember that there was also a small notch in the front bumper to provide some airflow as well.

The coolers themselves went through several versions. The early ones were just a simple loop (often called the trombone cooler) that allowed the oil to flow back through the lines back to the engine. However, the lines themselves provided surface area for cooling as well. Then Porsche went to the radiator style cooler, and finally added a fan to pull additional air through the cooler. In addition, there were aftermarket kits (Turbotrol by Lemke Design) that added a cooler to the early cars that did not have coolers (mid 70s if I remember correctly).

You are correct and that's what I was thinking in my head but failed to put in my original posting.. The guys that run their 911s during track days have an option to remove the right turn signal and add a scoop there for additional air flow.. not to mention- good luck fitting the Carrera cooler up in there...ya I though of that in the late 80's

[hasaramat]

I can't imagine that it is a matter of fender volume but of air flow. IMO only. The 911 had coolers up in the fender for many years, if it was a "bad idea" you'd think it would have gone away quick like the 1972 external oil tank door. As for stuff flying off the wheel that would be easily solved as in the Carrera. I was hopeing that someone was running this set up so I could see if it was worth the work. Lots of very smart and creative people on this forum, thanks for all the input and keep it coming.

[jd74914]

Any idea what the oil flow rate is or the length of tubing? And people usually use 1/2" or 3/4" tubing?

I do this professionally (well, not for cars) and to avoid running finite element analysis all the time, built a program for determining convective heat transfer in flowing systems. The original goal was to understand required line heater and heat exchanger sizing but it is applicable to the given problem.

If anyone is interested and can provide the above details, I can do a quick calculation assuming stagnant ambient air for the total heat loss in a trombone system.

Actually, a radiator probably wouldn't be too difficult to add so if anyone has any details about the later 911 cooler I can probably make a few program modifications and run that as well.

[GeorgeRud]

Most people use the 3/4 inch (though I've been told that 1" is probably better) braided hose. Don't know how much heat transfers through the hose compared with a metal tube, but I imagine that it's a lot less.

As far as room in the fender well, remember that a 911 is quite open in the front fender area as the headlight is mounted in that space. The 914 has a narrow area in front of the wheel as the headlight mechanism takes up that space and is enclosed in the front trunk area, leaving just a narrow space in front of the tire.

I don't believe there is enough room for a radiator-type cooler in a 914 fender.

[Eric_Shea]

Maybe someone should make a trombone for a 914 fender. (IMG:style_emoticons/default/wink.gif)

[Mark Henry]

Maybe someone should make a trombone for a 914 fender. (IMG:style_emoticons/default/wink.gif)

Or how about a brass jailbar cooler?
(IMG:http://www.914world.com/bbs2/uploads_offsite/forums.pelicanparts.com-26-1292219872.1.jpg)

[Eric_Shea]

That's the one I have in my 911. Too wide.