First Track Day-Overheated!
 

I am not new to this board, I just never have much to say. I need some help. Last week was my first track day and it was clear and sunny, the outside temp was about 90 degrees. After about ten laps, my 1979 stock SC started to loose power. So I checked my gauges and noticed the temp gauge was almost in the red! Oil pressure dropped to 2 bar so I pulled off the track and let the car cool down. After the car cooled down the oil pressure is back to normal and has full power. I have never had issue with overheating while driving on the street. Is this normal for a stock SC or do I have issues? Is it time to upgrade to a better oil cooler? Help

What I do know:
1) Trombone cooler is HOT
2) Stock SC
3) Never overheats in city driving
4) Timing is set correctly
5) Oil level is between full and lower mark

Any assistance would be appreciated. Thanks

Change your oil - now - and upgrade your cooler. Street driving does not equal track driving. First time at the track?

I would move up to a Carrera cooler setup and notch the bumper for airflow. I know a few guys in the area who run there SCs on the track with this configuration and it works well.

Jeremy, thank you, I will change my oil. Yes it was my first track day and I have a new appreciation for the skill required to properly drive around a track at high-speed. Or should I say, higher-speeds as just about everyone passed me. It was still a humbling great time

The hottest my 79 SC ever got was on the track. I also lost power but oil pressure was OK. Stock cooling system does not seem to be up to the task of cooling at sustained high RPMs. Does depend on the weather and the type of driving you are doing of course.
I have yet to upgrade as it really only seems worth the expense and work if you go to a front mounted cooler, but I would be curious what others expereinces are. Wonder if there are disadvantages in the cooling on the 78-79 vs. later year SCs?

very common to only overheat at the track. I think the trombone will never be suffucient for sustained lapping. Has any one had a trombone keep an SC cool on track?

Congrats then - it's addicting - and you get better, and smoother over time.

A front mount is a good route, but it's significantly more expensive than a Carrera setup as you must change to an aftermarket valence. The other concern (IMO) with a front mount is the practicality of it on a car that is driven primarily on the street. If you get in a minor fender bender or accidentally hit a parking lot curb too hard you run the risk of rupturing the cooler. The Carrera setup is the best choice. Personally, I run two Carrera coolers in circuit (one in each fender) to keep my 3.5 cool. Works great on the street and track.

I really wonder if an improved cooler will solve this problem at the level you're driving.
I know it feels like you are going fast, but I doubt you are abusing your car anymore than on the street.
This a Porsche so ....
If you oil pressure is dropping I'm thinking there's a flow problem.
My 2 cents worth.

I'm surprised nobody mentioned the problem with early SC's regarding the oil pickup screen. At prolonged high RPM the oil pickup cavitates causing exactly the symptoms you desribed. The fix is the updated sump plate and screen (I don't know the part numbers). I think the updated plate has no drain plug. Do a search; I'm sure there is info in the archives on this easy fix.

You may want to look for one of these:

http://forums.pelicanparts.com/porsche-911-used-parts-sale-wanted/233026-looking-updated-oil-screen-930-107-314-00-a.html

and...

http://forums.pelicanparts.com/showthread.php?s=&threadid=279038&highlight=930107 31400

You do not need a new sump plate, you can reuse the old one.

Just my 2 cents... I had the same problem with my 83SC when I was tracking it... I sold it, bought it back 6 years later, and it's still running hot on track and on warm days !! ;-)

The nice people who told you to get a carrera cooler are not wrong, but you should know that I have one, plus a fan, and while that definitely resolved the traffic jam overheating issues on 105F days, it still does nothing for track duties... Neither do a cool collar or that turn signal vent by the way... The one and only solution to get an SC cool on track in warm climates ? A front mounted oil cooler, that is pretty much IT. Or a swamp cooler mod (see other threads) ;-)

I am more and more convinced that people who say their car runs cool have a defective temp sensor ! ;-) My car has a new one and was calibrated to the gauge, verified by an IR gun, and I can tell it is incredibly sensitive to outside temperatures... Up to 70-75F outside, I can run all day all the time without a problem... In daily 90s in Florida, I run to the middle of the gauge just cruising on the freeway with the cooler fan turned on, forget track duties !! As soon as I find a valence I like, I will rig a front cooler and go back to Sebring ! MEantime, the Boxster's got the job (with the A/C on, no less) !

Howard and Ej11hhf thank you for the input, that sounds like the issue, hot temps and low oil pressure. I will check around to see if I can find one

And if you do go the front-mounted cooler route--I have a big Billy Boat cooler behind an IROC air dam on my modified '83SC--be aware that you'll have to do something to provide an outflow chute behind the cooler. Just plopping it up against the sheetmetal behind the bumper--i.e. the front of the trunk compartment--which lots of people do, is a huge waste of money. You're getting about 15 percent efficiency out of the cooler, with very little airflow through it.

I also agree with the poster who said there might be a flow problem. If you're running in the green group and getting passed by a lot of people, you aren't by any means running an SC hard enough to cause such extreme oil-cooling problems. Certainly you might see 210 or so on a warm day, but nothing like what you described.

Unless you're running in second when you should be in third...but your instructor wouldn't let you do that.

Stephan

After doing some research, does anyone know where I can get the "late Model SC Oil Strainer"?
Thank you in advance

Pelican Parts?

Stephan

If you're talking about pn 93010731400, it's a very tough part to find.

Start calling every used Porsche parts place in the US and post a WTB ad in the 911 Used Parts Classifieds here on Pelican. 93010731400 is NLA. That doesn't mean you couldn't find a NOS one though.

No, wait, I see it's "no longer available" at Pelican. Try Stoddard.

STephan