advice on warming race engine/oil temps

[mike the snake]

I recently bought my first Porsche race car. It is a beast, 3.5 with 13 to 1 comp. GE80 cams and 50mm PMO's, running Swepco oil.

At the events I've run so far, I finally got the oil temps above 200 by taping over most of the oil cooler, so I now know I need to watch that.

I want to get the car dynoed soon, and I'm wondering how long should I warm the car up before putting the engine under any load?

It takes about 15-20 minutes idling to get the temp guage to move at all, if at all.

Should I be at operating temps when I dyno the car? It might be hard to get the temps up to 200 without being on the track.

[TimT]

Drive the car on the dyno a bit to get temps up..

On our dyno we "drive" the car at medium rpm until the oil temp climbs. We add load and drive against it to hasten warmup...

Not sure if you can do that at the dyno you will be using


Before we had our own dyno and had to rent one.... we used to drive the cars around the industrial park for ten minutes or so to get the temp gauge to lift

[lucittm]

Mike,
It might be good for you to test your oil temp gauge with a mechanical thermometer of known accuracy because your high power engine should be able to warm up your oil pretty quick. There are too many cases of the wrong temp sensor being used with an electrical gauge.

Also, I would not want to let an engine like that idle for so long.

Good Luck,
Mark

[914/6]

tank heating pad
Moroso Blanket Style Dry Sump Oil Tank Heaters

[mike the snake]

Can I use a pyrometer to confirm oil temps, maybe pointed at the oil hard line?

The PO told me I'd need to tape the cooler up when I mentioned the low temps. It's a really big oil cooler.

I will confirm oil temps though, the car is new to me.

I also wonder about idling for too long.

I really want to do right by this engine, I'm sure it will last longer if I treat it correctly.

[safe]

Originally Posted by mike the snake

The PO told me I'd need to tape the cooler up when I mentioned the low temps. It's a really big oil cooler.

If it's done right it should have a thermostat, so it wont send oil to the cooler until the temp is high enough.

[mike the snake]

Yes the car has a thermostat. The car has run in this configuration for a long time, so I'm pretty sure everything is OK.

I felt the in and out lines, I can feel when the thermostat opens. There's a hard oil line that goes along the inside of the rocker, below the seat, and I've felt it by hand, and it's not above 200-220. Nothing tells me the car is running hot.

Maybe the guage is really slow? 4 gallon tank, would this make it heat up really slowly?

Oops, thermostat is to the left of the tank, just out of the picure.

[stownsen914]

How long does it take to reach 180 degrees during warmup for a track session? More than 5 minutes? I've seen race cars with large front mounted coolers and not even having thermostats that don't take more than 10 minutes to warm up to 180 degrees. I'd make sure your gauge is reading correctly. It's pretty easy to check. Just take the temp sensor out of the engine (it sits next to the fan) and make sure it reads about 210 degrees on your oil temp gauge when the sender is placed in boiling water.

Scott

[mike the snake]

With the cooler taped, it gets to 200-220 within ten minutes on the track. 10 minutes of idling just gets the needle off the pin-around 150. First time out the temps were 160. I began taping the cooler gradually, temps rose accordingly. Temps are now right at 200-220, and I plan to remove tape when it gets hotter. The PO said sometimes he taped as much as 3/4 of the cooler over, which is right where I'm at now.

I'm not sure but I think my guage and sender are different than normal. The sender is a fist sized unit in-line with the oil line where it exits the engine, mounted on the firewall just before the line goes forward, and there's a hard line going to the guage. I'll need to check if there's any wires going to the guage.

I will check this out and confirm temps next time I run the car.

Oil pressure is 90-100 lbs at idle cold. At 150-160 degrees temp, the idle pressure is still up there.

Only after the temps finally got above 200 did the idle oil pressure drop to 50-60. I considered this normal, and assumed I had finally gotten the oil to operating temps.

[Flieger]

When at operating temperature, you should have 10psi-15psi (1 bar) oil pressure per 1000rpm.

My car runs at the thermostat opening temperature (180*) on all but the hottest days. I have the above 10psi per 1000rpm oil druck.

I use Brad Penn 20W50.

[mike the snake]

I thought the 1 bar per 1000rpm was kind of a general thing for v8's, This is my first Porsche, but I thought they ran higher pressures.

Watching in-car vids of the PO on the track, the guages all read the same as when i'm driving the car, so I'm pretty confident that everything is OK, but I will definitely be confirming my temps.

[smokintr6]

When at operating temperature, you should have 10psi-15psi (1 bar) oil pressure per 1000rpm.

My car runs at the thermostat opening temperature (180*) on all but the hottest days. I have the above 10psi per 1000rpm oil druck.

yes at a minimum, but I have always seen higher pressures on my low time engines. It seems like they jump up to 4.5 bar pretty quickly and stay there.

[KTL]

Can you put a bung on the oil tank for temperature readings? I understand that the reservoir temperature is a good place to get your reading from. SmartRacing has a 1/8" NPT fitting on their front oil tank for the purpose of hooking up an oil temp gauge.

[tadd]

Nice looking tank setup. Very clean. Is that in the back seat?

Is the level 'window' PFA tubing? Polyfluoroalkyl starts loosing structural strength in compression at 200C (Teflon is another 50C higher). Yes, 220 F is not 200C, but you may just want to switch to plastic coated glass for the halibut.

You could easily switch the lower fitting for a 'T' and run a thermocouple into the tank thru the main run while the branch feeds the sight tube?

[mike the snake]

Oops, for got to mention it's a 914. It's more 911 at this point though

OK, I checked and the temp guage is mechanical.

The PO who built the car was a Master fabricator. The entire car is a work of art.

The car runs in GT2. Full tilt WEVO 915 gearbox, 18x13 rears and 16x10.5 fronts, JRZ shocks, ERP front suspension, turbo brakes, full carbon fiber body, cool box, the works.

Cars has gone 156 at Thunderhill, 125's at Willow Springs. I lucked out in buying this car, it is immaculate. It was also featured in Excellence Magazine, feature car.

I bought the car apart, needing carbs and ignitions, and I've put it all back exactly how Super Dave had it, and I've enjoyed 2 track days so far on really old tires.

It's now time for new tires, and to fine tune the engine on the dyno. I need to confirm the tune (it runs perfectly) and now that I'm getting faster I need good tires.

When I get fast, I'll go for a new corner balance, install the cool box and camera system, and go wheel to wheel someday.

Oil Tank is in front.

[Mahler9th]

Where are you taking the car for dyno work? Why? I'd ask Rob King about oil temps... or Rich/Jerry at JWE. You have a lot of relatively local expert resources that don't spend time on the internet.

What kind of tires is the car set up to run? If it is set up for bias ply tires, we have a group purchase going in the PRC.

Will you run the car sometime this winter?

Happy Holidays.

- Mike

[mike the snake]

Hi Mike,

Not sure where I'll go for dyno work, there's one at Sears Point I know, another in Rhonert Park. I just want to confirm jetting is good.

The car is set up for Goodyear Radials. I've found tires already for it, just need to pull the trigger.

Rob told me to idle the car for 20 minutes.

I've talked with Jerry and Rich, just haven't gotten too in-depth. I guess I should.

I'm planning on running the Feb 6th Trackmasters event at Sears, I plan to run as often as I can year-round.

[Mahler9th]

I think Pete Sorenson in Crockett may have a chassis dyno. If he does, his place might be an excellent choice. Of course for engine dyno in your general area, there's Rob and the folks at S Car Go.

I haven't priced the radials in a long time, many folks I know used to get used radials.... but I have heard they have become a little hard to find depending on the specific tire and specs. At least one nicely-developed 914 that runs with PRC has converted his set up to run to bias ply Goodyears, which are about $1k per set. There is/was a group buy on these in the PRC this winter.

Don't forget to mix in as much PCA-GGR as you can in your 2010 schedule. Most highly recommended for gaining experience and developing skills.

[EarlySport]

Love to hear your dyno results too when they're complete. A 13:1 3.5 should make some serious ponies.. :-)