Remote Oil Cooler Install Advice Needed MKIII With a 302

[ArizonaCobra1]

Hello everyone,I am the proud owner of a just acquired an MKIII coming from a cold climate to hot Phoenix AZ sun. I was out on a 95 degree drive and the oil temp was 220+. I definitely want to put a cooler in it myself so my questions are:
1. Just in front of the radiator at the bottom is an aluminum horizontal panel. Would I mount it on that or do I drop it to below to where the bottom nose intake is located?
2. Is there a specific dimension that is being used? I saw what I thought were 13" X 2" sized ones the had the "look" but I want to make sure it also serves the functional side first vs aesthetics.
3. Ones I researched online were in the sub $200 range. Does that sound right?
4. Lastly. Looking for advice on routing the hoses, what best to drill out the holes for the hoses with and where to get the grommets for the cut holes.
Apologies if this is a bit wordy.. Eric

[David Hodgkins]

I've been out in similar weather in So-Cal with my 302 and my temp never spiked that high. I'd make sure that there isn't another issue like air in the cooling system, stuck thermostat, fan not turning on or other cause before stepping up to an oil cooler.

IMHO... Good luck with it, and I'll be following this thread.

:)

[68GT500MAN]

Welcome to the forum and congratulations on your new roadster. Several of the forum supporting vendors sell an oil cooler kit that fits in the oval below the larger fan opening.
Doug

[Tom Mauldin]

28895
This is the kit that comes from Factory Five.i cut the holes with a bimetal hole saw and get the grommets from McMaster Carr.

[Tom Mauldin]

Ok that wasn't a good picture. Zoom in on the green car and see if that's any better.
2889628897

[Tom Mauldin]

The orange car has one as well but I don't remember if it is from Factory Five.

[ArizonaCobra1]

Thanks for the welcome!! Water temp is about 190. I figure it has a 190 thermostat. It's the oil temp that concerns me. . .
Tom, I'll look at the kit they sell. So you ended up cutting a hole that aluminum pan at the bottom of the radiator to drop it down?

[Tom Mauldin]

Yep, I cut the two holes for the inlet and outlet in the bottom aluminum and one on each side for the hoses to run through.

[Bob Cowan]

In general use, oil temp is usually about 10-15* +/- of water temp; usually plus.

The first question you'd want to answer is, what was your oil temp? Is your gauge accurate? Fortunately, that's an easy question to answer. With the engine good and hot, check the oil pan with a infrared thermometer. Should be a pretty accurate.

The second question is, how hot is too hot? 220* is not too hot for a good dino motor oil. And a true synthetic can easily run 250* all day long without a problem. Some oil cooler thermostats don't even open until near 220*.

The other problem with an oil cooler is, what do you do in the winter? Oil has a minimum operating temperature. That seems to be around 160* or so. Oil companies are not very forthcoming about that info. In Feb, you could drive all the way to Flagstaff, and still not see 160*.

If you really want to cool the oil down, consider a heat exchanger rather than a cooler. A much more functional choice for a street car.

[ArizonaCobra1]

Thanks for the input and more importantly, your knowledge. At this point I will research the heat exchanger option. BTW, the motor is a 1990 gt donor with about 110k but does run really well.
I'll update you as soon as I move forward.

[ArizonaCobra1]

Thanks for the photos too. I know perfectly how it needs to go.

[Tom Mauldin]

No problem. Any time

[CraigS]

While I understand your concern, as mentioned 220 isn't too high. Another thought would be to switch to synthetic oil to give you a better comfort level as we get into the summer and monitor the temps. One other thought is a big oil pan. My 8 qt definitely helps oil temp. Mine goes up sitting in traffic but comes back down quickly once we are moving again. If you decide to go w/ a cooler be sure to budget the money for GOOD quality ss braided hose and all the fittings. The dash 10 size stuff adds up the $ very quickly but is bullet proof. You may spend more on the hose and fittings than on the cooler. BTW if you have trouble finding grommets, get some 1/4 inch rubber fuel hose ore a heavy vacuum hose and slit it lengthwise w/ a knife. Feed it into the hole in the panel and cut it a 1/8 to 1/4 inch too long so you have to jam in the last piece so it's a nice tight fit.

[mikiec]

ArizonaCobra1,

2290 has been in the Phoenix area for the past 14 years. No oil cooler here. The temp's you are seeing are fine. Your oil temp needs to be hot enough to burn off impurities.

Where in Phoenix do you hang your hat?

Mike

[CraigS]

I forgot to add above that I have seen the thought that 220 is perfect. Just enough over 212 to evaporate and condensation that has gotten into the oil.

[ArizonaCobra1]

Mike, I'm in North Phoenix. Tatum and Greenway.
Craig, Is there a limit you don't want be at temperature-wise? 240, 250??

[68GT500MAN]

Found this in a Hot Rod article about oil temps:

For a dual-purpose car, engine oil needs to be at least 220 degrees F to burn off all the deposits and accumulated water vapor. For every pound of fuel burned in an engine, the combustion process also generates a pound of water! If engine sump temperatures rarely exceed 212 degrees (water’s boiling point), the water will mix with sulfur (another combustion by-product) and create acids that can eventually damage bearings.

As for ultimate power potential, the general consensus among most racers is that hot oil and cool water make more power in most engines. Cold engine oil causes excessive frictional drag on the bearings and cylinder walls. A quality conventional motor oil will tolerate oil sump temperatures of up to 250 degrees, but starts breaking down over 275 degrees. The traditional approach is to try to hold oil temperatures between 230 and 260 degrees. Even on a short-duration, drag-only combo where oil is frequently changed, I would not want to routinely see under-200-degree oil temps.

A full-synthetic oil will withstand sump temperatures in excess of 300 degrees, and for hard-core professional racing, some oval-track race teams are experimenting with ultra-thin, specially formulated, race-only synthetics operating at 350 degrees or even higher.

Also remember that a high-end engine is built as a total combination. Piston-to-wall clearances, piston ring end-gaps, and bearing clearances are specifically tailored to match the engine oil’s characteristics and intended operating temperature.


Read more: http://www.hotrod.com/feature_stories/1310_engine_oil_temperature/#ixzz31A56Xhhp

[ArizonaCobra1]

Wow! You certainly did some great work!
Puts me much more at ease knowing those kind of temperatures are normal. . .
I think now I will move on to other things on the car I want to upgrade in the future. Can't say enough how great a resource
this forum is.

[Bob Cowan]

Found this in a Hot Rod article about oil temps:

Read more: http://www.hotrod.com/feature_stories/1310_engine_oil_temperature/#ixzz31A56Xhhp

Although I would agree with most of that, certainly not all of it.

- Oil durability is a function of temperature and time. If the temp is 275* for a couple of minutes, that's not a big deal at all. But if it's a couple of hours, then it's a big deal.

- Oil temp does not have to be >212* to evaporate the water. This is a common misconception and internet myth. If that were true, your kitchen floor would never dry. Water will evaporate at anything >32* if other conditions are right. It just happens faster at higher temps.

- The amount of water produced as a by product of combustion is dependent on the amount of water in the air/fuel charge. If the humidity is 8 (like it frequently is in CO), you'll get a lot less water than if the humidity is 98.

- Think about the millions of daily drivers and work trucks around the planet. Oil is heated mostly by rpm's. But vehicles often cruise for hours with rpm's <2,000. Does the crank case get filled with water? No, of course not. Ever do a UOA? Not much water in there.

[CraigS]

Bob says;
"- Oil temp does not have to be >212* to evaporate the water. This is a common misconception and internet myth. If that were true, your kitchen floor would never dry. Water will evaporate at anything >32* if other conditions are right. It just happens faster at higher temps."
I guess I can't fault the logic there. That seems to make sense. OTOH, most of us have seen the milkshake that often forms at the oil filler area from not driving the car enough or hot enough. I guess it depends on the rate of condensation vs the rate of evaporation. Certainly water will evaporate a lot faster at a little over 212.

[Bob Cowan]

Right. And that happens Because the water is evaporating, and then collecting at the highest point - the filler cap. At lower temps, the water was vaporized. But there wasn't enough time for it to be cleared from the crank case.

Dodge had a hard time with that on their 5.2/5.9l gas engines because they were not vented properly. IIRC, the fix was a modification to the PCV system. I didn't have that problem with my truck, so I don't really remember what they did.

[hinoonaz]

Welcome to the Cobra world. I am researching oil coolers also. Thanks for this thread. I am not going to put one on my car now. I will find another place to spend the money. As they always say, "you are never done with these cars".