Jim @ EuroWerks

Who is not running cooling fans on a 944 race car. What problems can I expect. I would rather have them than blow coolant in a driver change.

SeaCay

Jim, can't answer your direct question, but I run my fans via both the thermal switch and a toggle switch on the dash. This way I have full control over use of the fans. I do the same with my turbo coolant pump. I would think you could get yourself into a pickle in short order if you are sitting in paddock waiting to get onto track, and are held up for some unforseen reason. I'd run the fans.

Jim @ EuroWerks

I agree, have you ever had to flip on the toggle. Or, is it just for a quik cool down.

M758

I direct wire both my cooling fans on my 944-spec car.

I had a problem with the auto on/off feature and figured manual would work better and be more "positive"

On cold days sub 60F I can run sometimes with no fans at all and run temp in the middle of the gauge. If it gets a little warm I flip the switch for one fan. Most 70F days I run both fans, but have run fine using just one. I have run in 100F temps and keep both fans going. The car runs warm, but not over heating.

I run straight water with waterwetter. Condeser is removed. Stock NA oil to water heat exhanger. I also cut the center bar from the front spoiler to aid cooling flow. This does seem to help with super hot weather days. I also us the stock undertray to maximize the engine cooling and run 5 blade fans vs the early 3 bladed fans. Stock 944 NA radiator, waterpump both fresh with a "Low temp" thermostat (70C)

HTH

RedlineMan

Here's another vote for fans!

I have both the original thermostatic and the AC fan switch systems in place. The rest of the AC inside and out is gone, as is all the spoiler webbing that was all cracked anyway. Took years for gravity to form that trick air scoop spoiler lip!

The hole in the bumper you see below is matched by a corresponding opening in the front core support. At least 20% more direct airflow to the rad. Fans are original, rad and water pump are probably 100k miles old.



I have a mechanical water temp gauge so I know what is REALLY going on. The Old Beast runs at 200 degrees steady in most weather 70 and under. On cold days I tape up the bumper. Only creeps to about 210 on the hottest days. Runs nice and cool!

I use the AC fan system when I'm coming into the pits. I flip them on once I get down to 30mph or so on the cool down lap. Keeps the car from heat soaking back up to where the fans would come back on after shutdown. I don't need to take LONG cool down rides anymore, waiting for the fans to cycle. Too busy looking for students or mentoring instructors to burn the time!

jerome951

I'd say leave the fans in. I've had to idle in the pits too many times for full-course black flags with minimal cool-down. I think you'd run the risk of overheating without them.

Sorry for hijacking this thread, but the fan wiring topic brings up a question I have.

My A/C system has been evacuated (leaking compressor seal that I've never bothered to have fixed). I pulled the AC relay, which I've been told will cause the fans to run on high (but not engage the compressor) when the AC switched is engaged.

Engaging my switch doesn't activate the fans, though they come on as normal when the engine gets too warm. Is there a low pressure cut-off or some safeguard in the AC system that would explain this? If so, I'll have wire a separate another switch to kick on the fans.

Car is basically a dedicated track car, so don't need the AC to work.

Adam Richman

If running an external oil cooler (like that mocal), I say ditch the shrouds and fans all together.

Jim @ EuroWerks

I don't know Adam you seem to be in the minority.

Jim @ EuroWerks

Ok Adam, we'll meet in the middle but cover all the bases. We'll wire it for fans but not put them in unless we see that we need them.

Adam Richman

Absolutely shocking I tell ya! <g> And to think I don't like Mobil One either

I think the wiring it for the possibility but starting without the assembly sounds like a good plan.

Jim @ EuroWerks

I'm sorry Adam, did you say something?

SeaCay

Jim, by the time you figure out you'll need the fans, it'll be either too late as in overheated, or too late as in you're in the paddock waiting to get going for your run group and realize that you need them without time enough to get it done. How about wire 'em up, put 'em in place, and then only use them if (actually when) you need them. Look at any of the race car projects that have been posted around here, all of them have fans. Control of oil temp helps, but it won't keep you from toasting your HG like water will.

And yes, I've used my switch to engage the fans while waiting to get going, and while slowly cruising through the paddock back to my "pit".

Jim @ EuroWerks

Good idea Thanks. I'm wiring them now.

RedlineMan

Jerome -

Yes there is a low pressure cut off for the AC system. I do not know for sure that this also effects the fans, but it does keep the clutch from engaging when there is no system pressure. In that light, I would reinstall the relay and see if the fans work.

You'll know soon enough how the system is wired when you do, eh?

Keep the fans, Jim. What's the point doing without them, anyway? I actually like the early fans better because you definitely know when they are on. The later ones are too quiet!

Adam Richman

runs cooler w/out the restriction of the shroud/fan assembly.

don't see any conceivable way you would hear a cooling fan running on an unmuffled race car.