Thought it was time to throw this out for discussion.......It would
seem that not many RM 944spec cars have been without some kind of
issue with temps on track, which can lead to the loss of oil pressure,
and .... you know the rest. What can be done ? What is the weak link
in the system ? How can we improve the cooling capacity, other than
hard wiring the fans and cutting away at the front of the car ? How do
the cars from AZ and SoCal prevent failures ? How can us high altitude
folks combat this ? How can all the cars that show up for a weekend,
run all weekend ? Let's figure this out (before I have a car to blow
up again !) thanks, Cullen

Weston was saying we needed to better burp our cooling systems ... besides that I plan on relocating my oil cooler and putting a fan on it. michelle's car ran cool as did Gary's ...

What cars can you fit the turbo radiator into ? Is that much improvement ?

My car typically doesn't get too hot...unless the radiator has a gaping hole in it like on Sunday afternoon. I don't have an air-to-oil cooler, either.

I thoroughly flushed the radiator and cleaned all the junk out of the fins on both of our cars, and both cars have new thermostats. Temps typically don't go higher than midway on the gauge. Oil temps this past weekend were 240F.

What I'd like to know is- what temperature does the DME back the timing off on the later cars?

Cullen, the turbo radiator is not legal as you must modify the car in order for it to fit.

Our thin dry air isn't very good for cooling things, so what's sufficient in other regions may not be sufficient for us on a hot day. The AZ guys on their hottest day still have denser air than we do on our coldest day, so our cooling efficiency is always going to suck.

Here are my suggestions...

- Keep your heater core, set the control on full hot, and point the vents away from you. I don't even notice the temperature difference with a fire suit on and the windows down, but it's effectively a second radiator for the engine. As far as weight goes, it's located near the center of the car, so removing it is not as valuable as taking weight out of other areas of the car.

- Properly bled cooling system. This is not a self-bleeding engine, so don't just fill it and forget it. A new thermostat with a bleeder hole will help, but it still wont do it for you. You have to burp it, get it hot enough to open the thermostat, jack it up so the air moves to the bleeder, let the air out, etc.

- Make sure your head gasket isn't leaking; they corrode and degrade over the years.

- Screen or wire mesh in front of the radiator to help keep junk off of it.

- Water Wetter

- Oil cooler. Reduces overall engine temps and helps protect your engine even if your water cooling system is shot.

- At least one upgraded radiator fan, with manual switches. My low-power fan will keep the temps good when the car is stopped, but I need more when racing and traffic is blocking my air, or when coming to a stop after a race. My high-power fan does a pretty good job, but it draws a lot of current and puts load on the engine, so I only run it as needed.

- The turbo radiator is cheaper than an aftermarket radiator and it works well. The problem is that can put a turbo radiator into a 924S without much trouble at all, but it's too tall for an early 944 without bending the lower mount a little (which the common interpretation of the rules doesn't allow). So, the 924S guys can use it, while the rest of us have to spend several times as much money to buy an expensive aftermarket radiator instead.

dmdirks wrote:


Only for us 944 guys, because we would have to cut and bend the lower mount a little. You can squeeze one into a 924S without doing that... in fact, Chris' fit easily enough that his turbo radiator pretty much fell out during Sunday's main race (we discovered that it had somehow lost it's top mounting brackets & rubber about 2 minutes before going on track).

Either way, no one can tell me that a turbo radiator is against the spirit of the class or the intent of the rules, seeing as how this is "low cost equal racing" and it's already perfectly legal to blow hundreds of dollars on a much better performing aftermarket radiator that was designed to fit in a standard 944. The turbo radiator is by far the most cost-effective upgraded radiator for our cars. They've also been easier to find used than NA 944 radiators.