Stupid question, what is considered proper running temp?
 

Just wondering, mine floats between 120 and 180. I know i i know im a dumb NEWB! lol

My '74 runs around 190-200 degrees during the MI summers and it has the external Carrera-style oil cooler. Your ambient temps are quite a bit higher than ours so I would expect your temps to be a little higher. Of course my temps are what the gauge is showing and I'm not sure how accurate the gauge is...

I was thinking the same about how accurate my guage is. Any AZ pelicans wanna ring in??

-Jeff

Not Arizona, but close by. My 75 ran between around 190 here in So. Cal. with the stock cooler, except on the hot summer/santa anna days at freeway speeds. Then it would pass 210, but never exceeded 230. I now have an external cooler w/o fan and rarely exceed 180. Again, relying on the gauge. Best investment I made!

Larry

Porsche considers 180 degrees F. to be the optimum "running temp." This, give or take a few, is where the thermostat opens in order to send oil to the front cooler in order to maintain 180. This is not to say that there's anything wrong with temperatures above 180--certainly any hard-used track car would see 200+, though 250 seems to be the maximum long-term limit--but cruising temps below 180 are considered by Porsche to be "cool," and we're not talkin' style.

If you drive a 911 "normally," i.e. nothing extreme in terms of pounding it, nothing extreme in terms of OAT, it is designed to stay at around 180.

110F desert, consistent 80mph, fender cooler, engine ran 200-210F. If i increased speed temp would climb.

Normal summer heat through Rocky Mt foothills is about 180-190F at 80mph.

Winter running is 170-180.

imo... if your at the margin with oil temps a single CHT will give you a heads up a few minutes in advance of a rise in oil temps. The biggest pia is bringing down the temps from excessive. Riding into the mts to hit la la land from the north on I-5 is a good example of keeping a heads up during a hot summer day. 5th gear will see cyl head temps rising so it's time to ride 4th gear before oil temps rise. Riding 4th at 3.5-3.8k rpm creates more fan cooling, less ring & bearing load, no wear on engine, and lower CHT.


being negligent riding up Independence Pass in Co during hot summer may generate very high CHT way before your oil temps lets you know what's happening. Just keep the revs up and don't lug for any reason.

In the summer , mine runs around the 9 o'clock temp position,
winter, around 7-8 o'clock. Engine seems to like cooler weather.

Dunno what the o'clock positions equate to any more, I have a numerical oil-temp gauge. But I think 180 is about eight o'clock, nine is maybe 200. So you're doing fine. The Germans don't know from summer, US-wise.

to get any 911 to run at 180 degrees in 115 plus temps is simply not possible w/out a fender and front oil cooler. since you live here and want to drive year round.........dump the bucks for oil cooler and lines. go w/a setrab for the front. worth its weight in gold. unless you have deep pockets for a new engine when stuck on one of the freeways.

doing 65mph on 118 degree day w/ac on 190. degrees. the best it will ever be. at the track in april on 85 degree day 200-210 degrees driving the snot out of it!

steve what exactly did you mean by the below 180 running temps. I typicallt run about midway between 120 and 180 on cold days 30 to 40 degrees. I have the front oil cooler and on warm days it runs at about 175 to 180. car runs great so I just assumed that was the ambient temp,but is there something I should check?

Troy, I'm not entirely sure what you're asking. Your temps sound fine. When I said below-180 is "cool," I didn't mean it was particularly bad. Obviously I wouldn't drive five miles a day at a well-below-180 temp, but I assume that's not what you're saying. Warm days at 175 to 180 sounds like the thermostat is probably opening and your front cooler is stabilizing the temps at that number, which is exactly as it should be.

Re: running cooler, FYI. I am running a 79 SC coupe with a rear 964 spoiler . When the spoiler is up/open, the engine runs ,maybe 10-20 deg cooler .Very suprizing and welcomed effect of bastardizing my car.
i also have the serpintine cooler and was going to upgrade it to a carrera cooler, but now I dont see the need to upgrade. .
Cant believe the difference.

Well, as far as what I am used to, and I live in New Mexico, my 74 911 runs at about 230 to 250 on 100 + degree days. In the winter months my car runs at about 180 to 210. I have an external oil cooler and I run the AC all the time. I'm not sure you can compare the temps to places like Oregon, New York or any place other than the SW desert. Dry heat affects cars much different than places with a little moisture in the air.

You need a bigger oil cooler.

Hey Steve! I'm not convinced a larger oil cooler will help the issue. When the air temps coming off the roads is 120 plus degrees, how are you going to get cooler temps from a cooler located close to the pavement? We don't get an evaporative cooling effect here in the SW. It would seem that the only viable option is to add a fan to the cooler. And that will probably only give you 5 degrees. I'd sure love to hear from other Porsche owners in AZ and NM. I'm thinking his car will run hotter in the summer months than it does now. Especially in AZ.

Add the oilfilter cooler? :D :D

With 230-250 degrees in the summer, I would seriously try to bring that down.
More ventilation to a bigger cooler?
Installing a fan?

Actually, dry heat is not your problem. It's the thinner air of high altitude environments. The thin air cools much less effectively. I have an RSR-style front spoiler cooler and it helps tremendously. Rarely get over 210F buzzing around the track in the Summer at engine speeds over 7,500 rpm (and 190F on the track in the cooler months)...

No oil cooler on my 2.4. I run 180 all of the time in Florida. At Sebring I can get to 210 if I'm running fast.

Richard

If I get behind one of those 35 mph speed limit types with auto trans, the temp gauge will creep up a bit.

Last summer, I got caught in an uphill line of classic cars waiting (too long) to get assigned spaces at a nearby Museum car show The SC didn't like it--no overheating, mind you--but the gauge did move up a bit. The "volunteers" at this show moving traffic left something to be desired.

Grant,

Do you have a part or model number for that rsr cooler? I'd like to check it out.

Elu, I believe that "RSR cooler" is a generic term meaning a wide, lateral, centrally-mounted cooler behind an RS/RSR/IROC-type air dam. I have one on my modified '83 SC, and it's a B&B, which seem to be well thought of. Other manufacturers make them too. They come in different sizes, mine is about 2.5 feet wide. You don't just pop 'em in, it takes some mods and work, including (ideally) a chute to evacuate the air from behind the cooler and lead it under the car, which I have; I had to cut into the trunk to install it.

I don't think the cooler itself is anything unusual, but the location works great (right in the airflow). Needs an RS/RSR style front spoiler. Mine is Carbon Fibre version from www.mashaw.com

Here's a photo of my car:
http://forums.pelicanparts.com/uploa...1173215560.jpg

Guys, try this thread, and others I have posted on.

http://forums.pelicanparts.com/porsche-911-technical-forum/334028-longer-fan-belt-revisited-cheap-hp.html



DeutschMark,

Yes, it costs power to keep the engine cool. Contrary to your proposition, there is a net power gain with increased cooling.

Oil temperature is a poor indicator of the important temperatures in the engine. In fact the oil temperature is the coolest in the engine. The critical areas are head and cylinder temperatures. These effect the power by limiting the air/fuel charge in the combustion chamber. Even more important the high temperatures shorten the life of the engine.

When you hear complaints of worn valve guides, the reason is excessive temperatures.


If you want to increase power for DE, try the “Rubbermaid Solution”.


Here in Colorado we have thin air (barometer 24” Hg) and it gets hot & dry in the summer. This has us at the forefront of engine cooling. Here it is critical. At sea-level it is merely VERY IMPORTANT.

Porsche reduced the cooling (’75->) to meet German noise requirements. The effect was to give 2.7s, SCs and Carreras too little cooling. All of these need the 1.82:1, 245 mm fans IMHO.

This is the reason why we (all Porsche racers) were at a disadvantage in the ‘70s against the Datsun 240s. They had water cooled heads and could use 14:1 CR. 10.3:1 was pushing it with air cooled heads.

The water cooled 911s have this better under control. Well, maybe.

Best,
Grady