I'm considering adding oil coolers behind my front fog light grills.

Who else has done this?
What's it look like?
Are you satisfied with the results?

OK... so why is it less preferable to do the oil cooler the proposed way as opposed to the open-mouthed GT way?

I know it's been discussed, don't know if anyone has done it. The two biggest drawbacks would be:
Size of cooler would be small, if you go to the trouble to plumb a cooler up front you want to get as much benefit as possible.
Where would you exhaust the hot air? There has to be good flow into, through and out of the cooler for it to be effective. The center of the car makes it easier to do.

Someone here (I want to say Brant) did two smaller coolers, each more or less through the bumper where the fog lights go, with ducting that took that straight into the wheel wells. The major downside is that the headlight buckets have to go, too. Not a very good setup for a street car.

I figure if you're going to do something different, be really different.

For a road car, or for AX, or even track duty with a mild-ish engine, I'm not convinced a "perfect" external cooler is required. Trekkor seems to do OK with almost no venting at all, he just put the cooler in the front trunk. Much like is speculated on 911s with "trombone" cooler, much of the cooling actually takes place in the lines. I would think a very intesting cooler setup would be a "surface" cooler, where you put hard lines with fins along the outside of the longs (or even just one long), plumb the oil to these hard lines with flex hoses, and there's your cooler. Loads of surface area, and the cooler isn't all that delicate or in a spot where it's likely to be easily damaged.

Another idea, convert the engine lid into a GT style, and mount the external cooler just below the forward part of the lid. There's certainly airflow here, and lots of otherwise wasted space. On your car, mounting it on the driver's side would probably be best, since you have all of your ignition stuff on the passenger side.

Yet another idea, mount it low in the engine bay, below the tin, near the firewall. If you're not running any heat, there's lots of room here.

If you are running heat, still another idea is to mount it atop a custom fresh air box at the base of the windscreen. I've seen this done, and the report was that it cooled the engine (a 3.2, in this case) adequately, but didn't generate as much cabin heat as desired. The lines to the cooler were run down the stock heater tubes, which dump straight into the right area for the cooler.

This is something we have onfile for use with Chillers.
http://www.wlv.com/products/products/Enhanced/HFTrufin.pdf

run it up one long and down the other maybe?
something i thought of.

Gwen,

Search for Brant's race car thread. He has an A+++, 5 star setup utilizing the fog light grills for the intake air. Extremely clean, effective setup. Brant would probably say it is too effective - I believe they ended up blocking one side off...

Thanks Ben!

so Gwen, I have a little experience in this area.
if you don't cut out your headlights and just run coolers against the body then your cooling is somewhat compromised.

Brad built Julius this way and the ended up running a 75 fiberglass bumper in order to move the coolers a few inches off of the body and get exit airflow.

without exit airflow coolers are hugely less efficient.

a PCA club racer budy of mine (car now owned by brian in AZ) tried a pair of fog light grill coolers without exits also. He ran PVC 5inch tubing from the driving light grill to the cooler, on a 2.2hot motor. but again with no exit behind the tiny mocal coolers that were approximately 1 inch off of the body.

He overheated badly at altitude.

he ended up giving up on the system and going with a front mounted cooler that had an exit.

my experiency on cooler exits on my old car led me to try 3 different exits with the same exact cooler. Each time I improved the exit, I dropped more oil temp.

you get something out of having the lines.

but you also get something out of having a functional cooler with a good exit ( larger exit than intake)

I did 2 huge coolers through the fog light grills on my 2.0/6 race car.
they work too much. I can barely get enough temp in the motor. But it's not streetable and I gave up my headlights.

overall... You will get something out of having the lines alone.
but if that something isn't enough then I would recommend a single front oil cooler with a good exit on a street legal car.

if you decide to go race only, then the fog light grills are neat as long as you provide a cooler exit into the wheel wheels and give up your headlights.

happy to talk at length and share my real life experience Gwen!
can provide pictures too.....

brant

Looks like these... http://www.elephantracing.com/oilhandling/oilines.htm

Dont know if they have kits for teeners but kinda $$$ tho.......

Gwen, I have an admittedly conservative view of oil cooling. I think you'd be sufficient with an oil cooler without any air flow. You could cut openings behind the fog lights just to introduce fresh air into the trunk. I like James idea of finned lines in the longs, but I think it's got a bit more R&D type work than I think you're looking for.

Not exactly...

My HUGE cooler sits in front of three large exit holes.
I use the front grommet holes as my inlets.

So, I have fresh air in and hot air out.

On a track car, this has to be done. ( unless you like short sessions )


KT

I saw a very different setup in an Excellence Magazine article of a red California car. The owner installed the oil cooler inside the rear, passenger side, fender just forward of the wheel...there is quite a large empty space in that area. He commented that oil temperature was more than adequate. A side benefit of this install is that the oil lines are kept short.

I will be installing a cooler in this manner. Bought a Mocal 914 kit from BAT in Florida. I also bougth the hose and scoop from AJUSA´s 911 front brake cooler kit to experiment forcing air from underneath the car to the cooler area.

was that a recent excellence article? do you know the issue?

I´ll answer your question tonight...once I get home from work. Its an article from within the last three years. If you have old magazines, look for an article on a red 75 or 76 914...the big issue with this car was that the owner installed a custom made FI using a Volvo TB.

hmmm ugmo has a scoop already!
Too bad it is UGLY AS SIN! and not one of the "fun" sins either! I always thought it would be a better spot for a cooler, roomy and protected. If you are running in a stock class, you might get dinged for non standard scoops...

Thanks for the help guys. I talked to Tony more about his recommendation last night. His reasoning for the design proposal is that it is streetable, doesn't sacrifice my full spare tire in the front trunk, involves the least cutting up of the car and protects the coolers the best.

BUT He says he hasn't done an ail cooler setup on a 914 for almost 10 years so maybe he doesn't know that the space under the headlights is too small for an oil cooler he couldn't give me a price quote either, because he hasn't done it in a while.

A co-worker who is also an ex-Porsche mechanic suggested mounting an oil cooler and fan in the back close to the oil tank under the trunk protected by the rear suspension. He says it would be a short plumbing job that will provide adequate cooling (not as efficient as fresh air), not blow hot air into the engine, and require the least holes in the car. Says he did something similar to his VW bus. Anyone done or seen this done?

Wes Hildreth in Dallas sells a kit that installs underneath the rear trunk as you indicated. It requires an electrical fan that is switched on-off manually from within the cockpit. I didn´t like the switching on-off part...the reason I am going inside the rear fender. This setup also uses short oil lines.

Seems inside the fender wells wouldn't protect the oil cooler from getting damaged I saw that the MOCAL kits for the 911s mount them in the front fender wells. Anything that gets picked up by the tires and flinged around the weel wells seems to be a threat to an oil cooler in there.

Does Wes have a website?

911 kits install in the front fender well....I am talking rear fender well using the Mocal 914 cooler kit. The cooler in this area would have to be installed sideways so the fins are not exposed to debriss. Besides, it is some distance in front of the rear passenger wheel.

Trekkor, that looks nice.
Is it working well?
You obviously aren't concerned about have the full spare tire available for street use. But is there any room left for one in your front trunk?

Ricky,
I'm still skeptical about the exposure inside any wheel well next to a spinning tire.

I believe Rich Johnson has an under trunk cooler with a fan, as well. One could easily switch the fan with a temperature sensitive switch, rather than manually. These switches are commonly available for use with watercooled engines, but can be used with oil just as easily. Most are also adjustable so you can change the temps they use to switch it on or off.

Placing it in front of the tire (as I believe was suggested) means it's unlikely anything will be thrown off the tire into the cooler. Behind the tire, then, yes, you'd have to shield the cooler somehow. The 911S put a cooler behind a front tire for several years.

Mid '70s 911's had brass tube oil coolers (coiled and multi tube - depending on the function and model) in the right front wheel well. They were more like heat sinks, not radiator types, and were much less susceptible to flying debris.

And they stopped putting a cooler behind the front tire because????

the "911" became water cooled

Basically their oil coolers a big coolant->oil heat exchanger.

James, I would think you would be well aware of the pummeling the inside of a wheel well takes when the car is shod with sticky race tires. No surface inside the wheel well is safe from gravel and debris being tossed up by the tires.

The gap on the passenger side inner fender well is a nice size, but there is very little air flow in there, it's pretty stagnant. Unless you cut a hole and add a duct, you're just gonna have a pocket of hot air in there, it won't make the oil cooler very efficient.

Mounting the oil cooler to the engine lid (minus the drip tray) is okay, better with a fan attached. But still has the problem of drawing low pressure air and venting that hot air into the engine bay.

There have been a number of installs in the rear under the trunck. Not bad, as long as it has a fan. But you're trying to cool that oil cooler with 125 degree temperature air. You're right next to the heat exchangers, the transmission and swimming in the heted air coming off the engine.

Up front is where the cooling is at. Even a tube-n-fin oil cooler up front (in the cooler, high pressure air) will be more effective than a mocal oil cooler wedged into the passenger wheel well.

Brant's setup is a work of art, In my opinion, it doesn't get much better than that. Then again, it's a lot of work and money to make something like that. I'm working on making a front oil cooler setup that works without cutting any sheet metal (not allowed in my class). I thought about the fog light grilles, but there's just no where for the the heated air to exit that area.

-Josh2

simple:

efficiency has some to do with SIZE of the cooler, but MOSTLY airflow.

do it once. do it upfront. never touch it again

Rich´s cooler is a Wes Hildreth unit....

Take a look at eastcoaster's thread. His cooler install is very very nice!

Yup, "Buy cheap, buy twice..."

Do it right the first time. Learn from other people's experience, it's cheaper...

-Josh2

yupperz.....

and you can always block off part of the cooler if it is too cool, but you cant magically get more cooling from a cooler that is too small for the job.

engineer a little bit of expansion capabillity

I'm not arguing more effective or less effective. I'm arguing effective enough. I'm also arguing trading off factors other than optimal cooling, like not wanting to run lines all the way to the front and back, taking up front trunk space, cutting vent holes, etc. Maximum thermal efficiency is not the be-all end-all solution.

Gwen's car uses a 2.2, which may or may not be in S tune (there's some doubt about that). It's primarily a street car. If she ran a front-mounted Mocal with full venting, my bet is her thermostat would be closed most of the time.

In my own case, I intend to try running my 2.7 with no external cooler at all. I'll be using an aluminum oil tank, so I'm hoping for some additional heat loss there. If I do end up needing an external cooler, I'll most likely try a simple cooler in the engine bay first, or even the along-the-long-trombone idea. Perhaps some louvers on the rocker valence for better airflow. I think the idea has considerable merit.

Granted I don't typically drive at altitude like at WCC, but I typically register 220 and at WCC I was a steaming 260

I'd like to go to RRC (UT) and next year the SWC (NM). I have been known to autocross and occaisonally do a track-day, but ya, it's mostly a street car. So I'd prefer not to sacrifice my spare tire and headlights....

Oh ya... I did get confirmation that my engine is a properly tuned 2.2S. I just don't have the S distributor or shroud.

I do like the open-mouthed GT look though

[gulp] What should this modification cost?

I don't think there are any off-the-shelf kits to do what you want, except maybe for the Wes (mumble) kit mentioned above. Rich Johnson can probably quote you a price on that.

The parts alone will be in the $300-400 range. No telling on how much labor would be involved.

the labor isnt "That bad". drill some holes, make some openings, buy a shroud

30 feet of -12 braided line at around 9 bucks a foot. (or you can go with the cheaper fittings and socketless hose)
GT shroud FG parts.... 100?
various fittings 100
mocal thermostat 100
Setrab/Mocal/Fluidyne/Mazda rx7 cooler - 50-400

Setrab/Mocal/Fluidyne/Mazda RX7 cooler

Is the quality of all these coolers equal?

I've been told offline only use MOCAL or Fluidyne and then by someone else that the Mazda RX7 cooler was definitely the way to go

Fun thread!

If you want to know if a spare tire will fit up front with a set-up like mine, try to set the tire on top of the spare cover instead of underneath.

I actually block some of the inlet holes in cold weather.
In 111 degree temps at TH after 25 minutes of *FLOGGING*, the temps creep up to 230-235. WhoooWaaa!!

30 feet of line will definatly do the job, but it's more like 24-26.
Fittings are $20-50 each
My BIG Setrab cooler lists at $440
Mocal t-Stat is $125ish.

It'll be close to a grandsky when you are all said and done.
If it's cheaper, hooray!!

Any car that sees serious track duty, *WILL* need a cooler. Period.



KT

The finned lines were used along the passenger side rocker panel by Riccardo Gonzales in Indiana, and they seemed to work well for him.

My 2.7 is cooled by a turbotrol cooler (Lenke Design) laid flat over an opening in the front trunk floor, with ducting bringing air from the front GT style bumper.

Back in the 70's, Porsche used the lines up the passenger side to the front hoop and back again. Basically, the front hoop was just a fancy U shaped detour to the back of the car. They figured that with the 55MPH speed limit, we didn't need any more cooling. No wonder the 2.7s had so many problems with heat!

I agree that there's no need to reengineer the system, the front coolers work very well as long as there is an outlet for the hot air! The lines are not that hard to run up there.

When I first bought my car it had a cooler under the rear trunk with a fan. It was adequate for the street but as soon as I went on track it was not cutting it as I quickly saw temps rise to 250+. If your going to run on the track you have to protect your engine, I don't think any cooler in the engine bay will be enough protection for the track.

tough decision!? So many credible seeming advice... front mounted or back with a fan

Then there's the decision of who to trust to do the work for me

Trekkor,
your setup does look pretty clean. Not sure about those huge outlet holes, but I undertsand the need to vent hot air out.

June 2004

Gwen, here are some pictures of the Gunnar Racing 914 with twin front coolers. This wouldn't be something you would want to do to a street car but it tell you what can be done.

Description of Rich Johnson´s car:

An Earls cooler is mounted under the rear trunk next to the starter. A custom bracket holds the cooler and the fan set (blows down through the cooler) about an inch off the bottom of the trunks floor for air flow to the two 12v commercial fans. Thanks to Wes at H&H Enterprises for this idea.

wont cut it for a track day.....

fine for street....

oil gets reaaaally warm at 20 minute high rpm sessions

If you want to see a really clean set-up, I will be showing my original six at the Carlsen Concourse this Sunday in Redwood City. I have a 3.2 motor with an external oil cooler mounted on the underside of the engine lid. It is a very efficient set up. The temp never gets much above 180 even when driving it hard.

Steve

When is this event? Is it at Carlsen Porsche? Have a pic of your car?

Yes it is at Carlsen Porsche this Sunday. I hope to have Dean Vanni there with his full concourse signal orange six that has one the Parade in the past.

Pics of my set up were posted a couple of months ago by Carreraguy. I will try to post again.

You should try to make it this Sunday and check it out.

Steve

Is this your car?