Charlie Stylianos

Background - 82 SC with Trombone style cooler and new Elephant Racing finned lines replacing the crimped original brass lines. The vehicle is an occasional driver (2-3 days week and want to participate in 5-10 DE events yearly).

I am still chasing over heating issues...I want to
make sure that the oil circulation/cooling system is in top order before diving into a full blown oil cooler setup (which I think is inevitable anyway).

Another 3 days at the track last weekend showed oil temps exceeding the 250 'too damn hot' mark again, even after line replacement, which did help (slower heat up times and faster cool down times). Max temp was very close to the 300-degree mark after 30-minute sessions, which I think, is reasonable for those conditions. But, I even saw these high temps during my commute to the track where I was caught in stop/go traffic in 90+ degree weather for a good 30-45 minutes.... is this typical???

**Interesting note regarding the finned lines:
About 10 minutes after a session I found a Porsche
mechanic who was willing to help troubleshoot my
overheating issues with a Pyrometer. The finned lines leading into and out of the trombone showed 180-degree temps, while the trombone itself showed 220-degree temps. This either mean that a) the brass finned lines are able to dissipate heat faster than the orig. lines, or b) the pyrometer was having trouble reading the temps off the oddly shaped finned lines, I'd like
to think a)

Questions:

1) Is there an easy way to test the external
thermostat to make sure it is opening all the way, as I know its at least opening partially since the trombone is hot? Or is this thermostat like an on/off switch with no 'in between mode’? Is the thermostat a usual a trouble spot? Should I also look into the pressure relief valve in the thermostat housing as well? Same question(s) apply to the internal thermostat and cooler.

2) I’ve been reading threads regarding the pre-Carrera 28 tube brass cooler being superior to the Carrera cooler due to brass' better heat dissipating quality, especially if air flow is limited. With a full-blown fender oil cooler setup, including fan, relay, etc, will the 28-tube brass cooler out perform the Carrera
style radiator cooler? If so, can the 28 tube brass cooler be used as a direct bolt in replacement for the Carrera style cooler, meaning using the same mounting brackets, shields, fans, etc as the Carrera style cooler, or will additional modifications be needed for mounting fans, shields, etc.?

3) I’ve been doing a lot of research and there are
tons of fender cooler options out there. If I’m going to do it, I want to do it right and do it once. If the general consensus thinks that the fender cooler wont offer the low temps I’m expecting (210-220 max), then I probably will go the front oil cooler route. I do not want to modify the car too much to keep it as original as I can, so I really don’t want to go with the new valance and front oil cooler setup. If there
is a 'best fender type cooler option' what is it?

Thanks again all for your time, effort and expertise. Hopefully as I tinker, gain knowledge and wisdom I can reciprocate.

-Charlie Stylianos
82 SC Targa (with Hot temps)

BER

I recently wrote a report on the Rennlist about my quest for lower oil temps. Here is that report:

"A couple of weeks ago I reported that I had installed an Oil Cooler Scoop
and would report my "scientific" finding after my next DE event. Here is
my report.

A little background first. I drove my '84 Carrera Targa (3.2 liter)in a
DE event at Lime Rock in mid-July. Weather was in low-90's and moderate
humidity. I have the OEM 28-row Carrera brass oil cooler mounted in the
RF wheel well. Oil temps during this event would occasionally hit 245
degrees (ouch!).

After that event, I did three things to hopefully improve oil temps.
First, I installed the numeric oil temp gauge and sending unit (my high
temps could have been from an errant gauge). Second, I installed Pelican
Part's oil cooler scoop into the front bumper; it mounts in the cut-out
for the RF side marker light. Third, while installing the oil cooler
scoop, I throughly cleaned my brass oil cooler with Simple Green, a hard
bristle brush, and elbow grease (I got the brass cooler shinning like
new).

My PCA Region just had a 2 day DE event at Summit Point, WV (last Thurs
and Fri). The weather was typical for the DC area in August...mid-90's
and very humid.

The higest oil temps I observed on my new numeric gauge were 225 degrees.
I can live with 225 degree oil temps on the track for brief periods of
time. The "scientific" conclusion is that the combination of the three
steps I took lowered my oil temps by 20 degrees! I do not know how much
the oil cooler scoop alone did, but it had to contribute to my lower
temps.

BTW, driving to and from Summit Point on the freeways (same ugly 90's
summer weather), my oil temp was a steady 195-200 degrees."

My experience with 911's is that the oil cooler thermostat for the RF cooler either works or it doesn't.

I have read reports from others that installed the Oil Cooler Scoop that it does not have a dramatic cooling effect on cars with the trombone loop cooler. You may want to consider upgrading to the 28-tube brass Carrera oil cooler and then install an Oil Cooler Scoop. If you get a steady flow of fresh air through the 28-tube cooler, it works pretty good. Another thing to remember, the Carrera's have a notched cut-out on the underside of the front bumper that allows more air to flow through the oil cooler.

Bruce

Elephant Chuck

Hi Charlie,

Glad the finned oil lines helped.

If you are seeing temps approach 300 in 90 ambient stop and go traffic, something is wrong. That is just too high even with the relatively non-effective loop cooler.

Baseline - make sure the car is tuned properly. Out of wack timing or lean conditions can make the car run hot.

I'd test your internal cooler for proper operation. These have problems sometimes and will make your temps shoot up. Test by puting your hand under the internal cooler when up to temp.

The fins should be too hot to touch, not just warm. If it is just warm, pull the internal tstat and test it on the stove in pot of boiling water. You should see it opening fully.

You should also feel air blowing through the fins from the engine fan. If no air, you have blocked fins from oil and/or debris. You need to clean that out.

The external tsat is not on/off. It opens gradually over a 10 degree or so range. I haven't tried it but I imagine you could test it on the stove, same as the internal tstat. It may be harder to see the action though.

How does your oil pressure behave? Is it low or erratic? Poor oil flow can cause overheating.

Before you replace the loop cooler, I'd first check everything above. A big cooler may only mask an existing problem.

The Carrera cooler needs air flow to work. That can be due to forward motion of the car, or a fan. The brass tube cooler does better when there is little air flow, but the Carrera is better when air flow is present.

That said, the loop cooler really isn't up to track level demands in 90+ temps. After you make sure everything is operating properly I think you will want to go to the Carrera cooler.

Charlie Stylianos

Bruce,

I was hoping I would not have to go with the front mounted valance and cooler setup to bring my oil temps into my 'happy range' of 210-220 max. The more I read, the 28 row cooler looks to be more effective than the carrera cooler, espically if the air flow is there.

Regarding finding and mounting the 28 row cooler, will the 28 row cooler mount with the carrera brackets? Can a fan, thermostat and relay be added to the setup? Can you be more specific as how (brackets, body modifications, ect) you mounted yours and where you acquired it?

So it looks like my external thermostat is working fine, so I should look to my internal thermostat for problems, I'll to the touch, ouch test.

I'm hoping with the finned lines (already in place) and the 28 row cooler (with fan, that would be a bonus) should get me to my happy place.

More thought, suggestions please...this is good stuff here.

-Charlie

Charlie Stylianos

Hey Chuck...I think I talked to you when ordering the lines a few weeks ago, howdy....

I agree that sitting in stop/go traffic should not cause the high temps I saw, so I definitely want to find the root cause of my overheating issue before masking it with with an oil cooler. But if I'm doing track events, an oil cooler is enevitable. So I guess this is a 2 part post.

Prior to this DE event, the valves were adjusted, engine timed and A/F mixture was set using the dwell meter method. Also replaced plugs, cap, rotor, wires, filters, etc. So I think the engine is in the best state of tune since I owned the vehicle (and it runs sooo much better). BTW: The overheating problem was an issue prior to the tune up.

Once the car is warm, about 200, and even hotter, the oil pressure to rpm rule applies (1 Bar per 1000 rpm, give and take a little depending on how hot the oil is). So the oil pressure does stay up...which is good.

hmm...soo many theories regarding the Brass/Carrera cooler.....more thoughts please, dont't want to do this upgrade twice/thrice....

-charlie

BER

Charlie,

My 1984 911's 28-tube oil cooler was standard from the factory, so I have no experience mounting one in my car. Based on what I see in my RF wheelwell, it looks to be a fairly straightforward mounting setup. I could add a cooling fan if I wished, but with my current setup, my oil temps are fine. The only time I would need a oil cooler fan would be sitting still in traffic; fortunitely that does not happen very often.

Have you read the tech articles in the "911/964" section of the Rennlist Tech Discussions? The link is:

<a href="http://tech.rennlist.com/" target="_blank">http://tech.rennlist.com/</a>

There are a couple of articles about external oil coolers that may answer more of your questions.

Chuck is right about 300 degree oil temps - way to hot! Something else is wrong if you are seeing those temps even briefly. Just a suggestion - have you considered retro-fitting your car to a new numeric oil temp gauge and matching sending unit? Your gauge could be giving erroneous temps. A new gauge will not eliminate high oil temps, but will give you a more accurate picture of what is going on in your engine.

Bruce

Alan Herod

Sorry to be the bearer of somewhat bad news concerning the proposed 28 row cooler. I was at the same event that Bruce mentions driving a white SC in Red, 546. I mention that because some folks came by to look at what I had done.

On the track oil temp rises to about 127C (260F about 1/4 of the way between 120 and 150) and stops, on the street in stop and go in the same temperature condition, the temp stops at about 100C, while oil pressure remains within tolerance. Normal street driving, about 90C, if that high. I have the gauge with a white mark at 90C (194F), 120C (248F), and the start of the red area at 150C (302F). Some have defined the 28 row cooler as a heat sink and do not consider it effective at dissipating heat.

This data is with the following modifications:

Removed the parking light and moved the turn signal to the parking light position, resulting in a large opening in the front of the bumper.

Notched the underside of the bumper, larger then the Carrera notch.

Removed the headlight and cut out the back of the headlight bucket and replaced the headlight without the trim piece between the headlight and the bezel. Seems to mitigate the need to remove the headlight which does not contribute to further reduction in temperature.

Faired from the front valance to the cooler so that air coming in the openings can not spill over, around, or under the cooler.

I blocked off the headlight washer on the driver's side and ultimately relocated the remaining nozzle to in front of the cooler and exhausted all the ice water with negligible effect on the temps.

I do not believe that the Pelican scoop will contribute to more airflow then the changes that I have made thus far. With that in mind, I believe that anything short of a radiator style cooler in the same location will not significantly impact cooling to the degree that you are looking for. With these temperatures, always run synthetic. I believe that a 41 row Mocal cooler could be effective in the fender location if there is sufficient air flow in that area but I have not measured the air flow yet.

Bill Gregory

If you haven't already, you might read the article on 1989 and earlier 911 cooling on tech.rennlist.com. On my 81SC, I went from the loop to a fender-mounted Earl's radiator cooler, to adding a fan, to a front valance mounted cooler. Before adding a fan, I cut holes to bring air through. It wasn't until I went to the front valance mounted cooler did my heating problems moderate to a reasonable state (190-210 degrees). I would forget about the brass cooler. Someone else posted recently that they went to it, and while it was an improvement, it wasn't enough to overcome the heat stress in a track environment. Of course I checked everything else, ie, engine wasn't running lean, thermostats worked, oil was flowing properly, no bent oil lines, etc.

Stephen Masters

Charlie I am having the exact same problem as you with my 1978 SC. I have installed the new oil cooler and drilled holes in the headlight bucket and still got "to damn hot" I even replaced the sump pickup and am in the process of replacing the thermostat insert.

SO if you find any answers please let me know.....

Thanks Steve

Charlie Stylianos

Bill,

Is there a good source for a new/used front valance and oil cooler. Can I find this in a kit similar to the pelican 'super dooper' carrera oil cooler kit? The more I read, the more I think this is the correct solution. Can you be more specific as to how the valance bolts in/fog lights (can I keep the originals?) and oil cooler setup/lines running to the front fender.

Thanks again.

Alan Herod

It seems there is no question about the direction that you would want to go for a track car. But if you have an SC or an early Carrera with airconditioning and a center mounted condensor, and want to retain the airconditioning, you might need some other solution. My compressor gave up the ghost, but I have not completely given up the idea of upgrading the compressor. It seems like the condensor would be on the wrong side of a front mounted oil cooler.

Bill Verburg

Bill Boat was using one of his fender mount coolers w/ fan on his SC w/3.6, this was in Az. w/ ac. When I spoke w/ him about it he was very happy, reporting temps under 210F at all times. Nevertheless a bumper mount is the best way to go. I have seen small bumper mounts that didn't entail the large central opening. They are used in series w/ a good fender mount and seem to work well for PCA racing in E and F class.

Martin S.

I have an article in the Rennlist Tehnical section as well as Pelican Auto Parts...that does not make me an expert, HOWEVER, I have spent thousands of dollars chasing the problem of excessive heat, which means that I am just like lots of SC and 84 to 89 Carrera owners. I started with the Trombone, went to the Turbatrol, dumped that and went to the 87 Carrera Cooler with an active fan, the Carrera valance with fog light and parking light removed, the properly notched bumper...that wasn't good enough. I finally ordered and had installed the front mounted cooler around a 934 type fibreglass front spoiler. I also added the new sender and the numerical gauge for the oil temps. Bottom line, the B&B set, or something similar in size and quality, works, no ifs, ands or buts. In the high desert in CA (Willow Springs) in July, after 20 minute run sessions, I never saw any temperature greater than 215 degrees F.

I have been observing various SC and Carrera owners wrestling with this problem for years...the front mounted cooler is the only solution I have seen that works when it is really hot out there.

BOTTOM LINE: Just quit fighting it. If you want to do it right, you get the B&B front mounted cooler from Billy Boat at B&B in Phoenix, or a similar product from another vendor. Bolt it to the tub, hook up the oil lines, and now add on a 934 type front valance. Most manufacturers of fibreglass sell these spoilers. I don't work for Billy Boat, and I don't sell fibreglass. I just want to see you folks running hot, to cure your problem, and get on to something else such as driving for 20 minutes at speed, in the heat, fully confident that your car will run cool. This is my mission today, and tomorrow as well.

I like the idea of the finned oil lines...they must help by providing an expanded surface area for heat to sink away. However, in racing conditions, you will need a front mounted cooler. AMEN!!!!

Steve W

I have the 28 row brass cooler in my right front fender and just bought a used 89 Carrera cooler with fan and all the shrouding today. I was just going to try and exchange one cooler for the other, but got to thinking about running two fender mounted coolers. I could place the new 89 Carrera cooler/fan in the right fender, remove the water bottle in the left front fender, and place the 28 row cooler there. Then plumb up everything is series. Has anyone considered, heard, or done anything like this? If no one thinks it will work, then my 28 row cooler is up for sale.

Bill Gregory

[quote]<strong>Is there a good source for a new/used front valance and oil cooler. Can I find this in a kit similar to the pelican 'super dooper' carrera oil cooler kit? T Can you be more specific as to how the valance bolts in/fog lights (can I keep the originals?) and oil cooler setup/lines running to the front fender. </strong><hr></blockquote>

Here's what I did, and it's not the least cost solution, but, for me, the best. I went with a RUF front valance and a RUF oil cooler. The RUF front valance is made from Polyurethane, and gives, unlike Fiberglass which cracks when hit. This was important because my daily driver is what I use on the track, and the roads in the New England area go at every which angle. So the lip hit the road a fair amount - sometimes hard to judge and avoid. My SC was also fairly well lowered. The RUF oil cooler is slightly curved, which fits right into the valance. It flows the oil from right to left (as you're facing it) which produces maximum cooling (as opposed to a cooler that flows the oil top to bottom, where alot of oil gets a little cooling). The RUF oil cooler came with the oil lines and fittings to hook right up to the hard lines in my SC. I may have used one Earl's fitting to help with the angle on one hose, but probably could have gotten by without it. The hoses are the right size, around -16an, or the same as the Porsche brass lines. Here's a few pictures of the valance installed on the SC:





You'll note I didn't have fog lamps, rather I ran ducting to the brakes. The RUF spoiler comes ready to accept Carrera (84+) fog lamps, however, you might want to verify that with RUF (84+ vs earlier fog lamps). You can see some scratches on the bottom lip. That I painted with Rustoleum flat black, so a spray every now and then restored things back to like new. Plus, painted black, the lower lip kinda wasn't so obvious.

Of course, when I put the front valance on, I had to put a rear wing on for aerodynamic balance - don't do one without the other (There's a good discussion in Paul Frere's book on what happens when you have a front valance w/o a wing and vica versa). I chose a Mike Shaw fiberlass wing. Here's a picture of it, unpainted:



So, what did all that mean? It meant that my temps stayed in the 190-210 range. Probably the hottest track I ran with it was Watkins Glen in July, and it didn't break a sweat. Only took me about 6 months to stop watching the temperature gauge. Excellent combination polyurethane front valance and RUF cooler, coupled with the wing on the back. Made for a well balanced 911 on the track, and I noted more stability at highway speeds. Cost was around $1100 for the valance and $900 for the cooler. I ordered directly from RUF in Germany.

Anyone has questions, please let me know.

PS. Martin wrote a good article on coolers too, so there's another good source of information.