jturbo

I have the following engine modifications that I bought through Powerhaus in Arizona.

O-ringed, ported and polished cylinder head.
Autothority Mass Air Flow Unit
Autothority Computer chips
K27-8 turbocharger
993 Recycling Valve
Tial 46mm Wastegate
Cone K&N Air Filter

And a lower temperature thermostat to handle the extra heat that the engine now produces.

Since I have not been able to get in contact with anyone from Powerhaus (Not sure if they are still in business) I have no way of telling what temperature thermostat that was installed.

I know it was a lower temperature than the factory, but not sure what the temperature was.

Any ideas. Or is anyone running a similar set-up?

jturbo

Is the thermostat temperature stamped into the thermostat?

MAGK944

Yes. The thermofan switch is also stamped and is easier to read. If the job was done correctly, a lower temp 71 thermo should have a higher 75 switch and a 80 thermo should have an 85 switch. So, the switch temp should determine what thermostat you have fitted, in theory anyway.

V2Rocket

The thermostat has nothing to do with "handling the extra heat".
All a thermostat does is set a FLOOR for coolant temperature, not a CEILING - that is determined entirely by the effectiveness of the radiator rejecting heat into the air.

Luckily the standard 944 Turbo radiator is very capable, even at very high power levels.

Changing the thermostat temperature only changes at what temperature coolant is allowed to flow from the radiator into the engine.
Ideally you'd run the highest temperature thermostat available which IIRC for the 944 is 95C/203F. Hotter coolant (to a point of course) helps keep oil and fuel from sticking to the cylinder walls and makes the engine run better and cleaner.

jturbo

My 944 turbo came with a 180 degree thermostat, but that will overheat the car. I can't find the records that say which thermostat I bought after going with all of the performance mods.

Some have said that the 160 degree thermostats run too cool. Does anyone know how to get in contact with David at Powerhaus?

Thom

Stick to a stock 83°C-stamped Wahler thermostat.

V2Rocket

If you are overheating it's not the thermostat's fault, unless the thermostat is stuck closed.

rlm328

^^^^^^^

What spencer said. I am running a 83 C thermostat.

If you are running hot I would look to a HG issue.

jturbo

What is an HG issue?

rlm328

Head gasket (HG) failure. One of the symptoms of HG failure is high water temps. During the HG failure the cylinder will out gas past the gasket and get into the coolant system super heating the coolant. The failure is initially one way. You will not have water in the oil, water in the pistons, nor oil in the coolant. If you take the radiator cap off when the engine is running you can sometimes see gas bubbles in the coolant.

Tom M'Guinn

+1 on what others are telling you. HG=head gasket. If your car is overheating, that is not due to your thermostat temp choice, and lower temp thermostats do not increase the cooling capacity of the system.

Is your car overheating? If so, I'd start by venting and pressure testing the system to check for external leaks. Don't know the status of Powerhaus these days, but if you are determined to know what temp your thermostat is, you can remove it and look. It will be stamped on the metal.

jturbo

Thanks for the input guys. Actually I am not certain if the thermostat was ever replaced by a lower temperature thermostat. I was my recollection that it was a lower temp, but I'm not certain.

The problem that I am having with the car is as follows:

I was parked and let the car idle for about 10 minutes. All of a sudden I could see antifreeze slowly pouring out of the passenger side front bumper. I was able to get the car home without overheating the car. I tried to start the car the next day and a loud shrill was coming from the engine.

I am not going to try to diagnose the problem. I am going to take it to my local Porsche dealership to have the car serviced and let them tell me what is wrong with the car. (I realize this might be dangerous as they are probably a lot more expensive than an independent shop that works on German cars.)

What do you guys think might have happened?

Tom M'Guinn

You might have an external leak letting air in the system. When the car warms up, that air expands and pushes out yet more coolant. Or the fans aren't working, causing the car to overheat when not moving, but act fine when driving and getting plenty of flow. Or could be a dozen other things...

rlm328

Sounds like the water pump gave up the ghost. A real PITA in these cars to get to.