Operating Temp?
 

It's starting to warm up (HOT) here in Florida, and I've noticed that the car is running warmer now that I have the A/C fixed.

When I didn't use A/C, the engine would never get above 190*. Now that I'm using the A/C all the time, the temps are getting above 210*. Will running at 210* to 220* cause any issues over the long term? I know Bruce Andersen say 250* is "too damn hot," but how hot can these motors run without any problems? I'm sure it would be better to have the temps below 200*, but it's really not an option here in Florida unless you have serious oil coolers......

I have an aftermarket cooler without a fan, and was wondering how much of a difference with factory cooler with temp controled fan would make. Anyone?

210 is not too hot. I remeber some past posts saying that 190 is too cold. I think you are at a safe temp.
An electric fan on the cooler can drop the temp about 15-20 degrees.

180-190 is the ideal temp for maximumizing engine life. According to Bruce Anderson, 220 is the upper boundary acceptable for routine driving.

Bruce says "230 is warm, 240 is hot, 250 is too damn hot".

The fans help in stop-and-go but don't do much at highway speeds.

What typically happens is the engine temperature will rise in stop and go driving, but it doesn't seem to want to come down once I'm cruising again. It's almost like it get to a particular temperature, and stays there.

I wonder if I should upgrade to the Carrera cooler and temperature controlled fan? It doesn't seem like it would that horrible to install, would it?

If you're still saddled with the loop cooler, then yes, the Carrera cooler would be the most obvious upgrade. At the same time, check to make sure the oil lines aren't mangled, and that the onboard oil cooler is working properly. Sometimes schmeg gets sucked in and clogs it up.

If that's still not enough cooling, you likely have other issues - ie mixture and/or timing. If all that checks out, and you really want cooling, then check out http://vintagebus.com/howto/bumper-cooler - this is almost (but not quite) the ultimate street cooling setup.

http://vintagebus.com/howto/bumper-cooler/MVC-395S.JPG

Depending on what cooler you have now, the Carrera cooler might be a good upgrade. It is a very good cooler, although some of the large aftermarket coolers are good too.

Thom, I'd suggest the valance cooler was a good choice for you since you have a 3.6 (needs lots of cooler) and track your car. But it is not the best for a street car, especially with a smaller engine. High cost and fabrication complexity aside, a valance cooler hangs low and way out front, just daring parking stall blocks to mess with it.

Michael,

One thing that needs to be addressed is what kind of oil are you using! Dino oil starts breaking down at a lot lower temp than syn oil so if you are using Mobil 1 (for instance) then you are ok for another 30 degrees on the temp gauge.

If you are using dino oil I would keep it 220 or lower and if it starts to go over this then turn the a/c off. A better oil cooler, fan and ducting will help in this area. Porsche did not duct the air very well to the stock cooler and the setup that Chuck has done is a lot better from a cooling standpoint.

Joe

For those of us with the newfangled gauges that only have hash marks instead of temperature marks, is the translation as follow?:

180- top of the lower wide hash mark

210- lower narrow hash mark

250- upper narrow hash mark

:confused:

Is this the 9:00 o'clock position?

Paul,

Go here for a picture:

http://forums.pelicanparts.com/porsche-911-technical-forum/70344-oil-temp.html

I upgraded my gauge and sender to the earlier version with the numbers. The only thing I don't like about it is that the numbers are covered slightly by the primary gauge face, as the opening isn't big enough to accommodate them.

[img] http://forums.pelicanparts.com/uploads/temp gauge.JPG[/img]

I'm using a radiator style aftermarket cooler without a fan. My oil lines are slightly crushed towards the front, but not enough to cause a flow problem (I don't think).

Does anyone make a temperature controlled fan that can be added to aftermarket coolers? Maybe that's the route I should take. I don't want a switch controlled fan.

Dang it......Here's the picture.....

http://forums.pelicanparts.com/uploads/temp gauge2.JPG

SeaDweller,
I don't suggest switching over to a synthetic oil just because this lubricant remains more stable at 250ºF. You don't want oil temps. this high regardless of the oil type you use. Parts with different coefficients of expansion begin to grow at elevated temperatures. If you get it hot enough, clearances will decrease and parts will be susceptible to scuffing and galling - not good.

Install a 5 1/2" Spal pusher fan or equivalent onto the cooler. Install a Hayden adjustable thermostat to automatically control the ON-OFF switching. You can get the switch from your local auto parts store or mail order from JC Whitney, Summit or Jegs. The temperature difference will be most noticeable at idle and stop-and-go driving conditions. If it still gets too hot (+230ºF) you may have to switch the AC OFF.

Sherwood Lee
http://members.rennlist.org/911pcars

Yes, you're right. Not everyone is as willing to take saw and welder to their car as I am...

What do you guys think about installing a Spal fan on the 29 row brass tube type cooler that come on on the earlier 80s Carreras? Or by even doubling it up by placing two of these coolers in series or parallel in the stock location? I think it was Bruce Anderson who said that this type of cooler was better suited to US driving conditions than the later radiator type because it was not as dependent on air flow for radiating heat. My oil has gone to 230 on a hot day with the AC on in stop and go traffic.

warm weather driving
 

As I read Michael's initial post I recalled that his oil temp experience is similar to mine, in that it may take a while to reach 180-190, but when it does reach it and go over, say 210, the temp does not go down quickly at all-- either idling or at highway speeds. Turning the engine off for a while is the only way to get the temp to drop back to the previous zone.

My engine is new (rebuilt), with a brass tube style cooler up front and clean/working engine cooler and lines. There is also a new thermostat. I don't recall the opening temp for the thermostat. My take on the 3.0L is that it takes a good while to reach operating temp, but when brisk driving, environmental temps, or engine loads (A/C) push the oil temp to 210 and beyond the system isn't designed to dissipate heat all that quickly.

Since you already have a cooler up front, one or two fans are what you may need. Air flow (passive) ducting only works when he car is at speed, so setting up a fan with an automatic or manual switch gets the radiator working much more efficiently. Just as you discovered with the physics of A/C-- air flow is key.

My .02