Hey guys,

Summer is approching fast here in Texas and I can expect 90-100 degree temperatures. My question is this. My car is modified and well I dont want it to overheat considering I will be using my A/C a lot.

I used to have a manual fan setup but i think i want to go with the PCM turning it on at about 210 degrees until it cools down to 200.

Do the fans have a certain speed setup like Hi and Low?

what year?

1995

I think those had the series parallel trick that acted like two speeds... check the helm to be sure.

To be honest, the dual fans used on the LT1 are VERY good.

If you are concerned about over heating, I would consider upgrading to a DeWitts aluminum... or at the very least, be sure the center air dam is good, otherwise the bottom feed won't get enough air sucked up.

The big mouth air dam can help, too.

Thanks Bogus,

The reason I ask is because I had a manual fan setup because I took my car to the track and woudl turn it on to keep my car cool.

The track closed down and it was the only "legal" one and haven't gone there in a long time so i thought about having it come automatically. I just didnt like the fact that the fans turned on when the car was really hot. I dont remember the exact temps but basically I just want to keep my car as cool as possible.

On at 205 and off at 185, with a 180 stat, is what I run with. My settings are as cold as I would go, I might even bump up to on at 210 and off at 190 or 195. There are many varying opinions on this, just make sure you don't get too cold on the settings or your fans will run WAY more than necessary and accomplish nothing more. My fan runs a little more than necessary which is why I might bump up. It isn't severe, just occassionally in the heat of the summer on a 45 mph cruise it is running and I know the car isn't going to get down to 185 for it to kick off. CFI-EFI has always seemed to give good advice and possible settings on fan temps, maybe he will chime in.

Thanks dan0617. The proposed 210° on and 200° off is a good starting point. A lot depends on the thermostat. Like Dan said, his 185° off temp is a little low, especially if his engine wants to run at 185° to 190° on summer days. I have a 206° on and 196° off, with a 180° thermostat and my fan rarely runs. As an illustration, if Dan had the stock 195° stat, his fan would never shut off. With his 180° stat, 195° to 200° would be a better shut off temp. Also a spread of 10° between the on and off temps seen to be a smart minimum. I thought of posting earlier, but I don't know exactly how your two speed fans work.

RACE ON!!!

It should be covered in the FSM. If you don't have the FSM and the 95s are the same as the 96s, then I could scan the appropriate section out of the 96 FSM and email it to you...

I had my own version of the "Big Mouth" that I just removed today because it had become overkill. Plus I was getting tired of straightening it! In my modified LT1 I use a 180 stat and fan on temps of 185 and 200. With a DeWitts radiator, they don't run except in traffic or during sustained hard use.

If you want to email me your .BIN file, ill set the fans up for you. There is a fair few parameters to set on 94/95.

185*F shut off is way too low with a stock thermostat, the service manual states running teperature is 201*F. The parameters for fan control are all adjusted in METRIC and not imperial.

The 2 separate fans are controlled independently, on default settings, both will come on with the A/C and stay on as long as its turned to an A/C setting, even at higher speeds, which is not needed. You must reach 83mph for fan 1 to cut off while the A/C is switched on, and fan 2 will cut off at 80mph. There is a 3mph hysteresis for both fans.

There is a setting for higher speeds as well as lower speeds, and by default, it switches to the higher speed settings at 0mph, which renders the low speed settings useless.

Changing your fan settings isn't going to keep you from overheating.

You can only do that by increasing the heat exchange capacity. Bigger radiator, more fans, more air, higher temps, etc.

Now, if you just don't like seeing 220F or 230F on the guage, that's an entirely different story. But it'd be easier to just put some tape over the dash guage. :thumbright:

Quote:
Exactly

Was watchin' "Auto Shows" on ESPN this weekend. They were at the "Be Cool" manufacturing plant. The CEO and some of his guys had 5 or 6 of their personnal Corvettes sitting out front with Be Cool settups on them.
They showed a little data on the temp reductions thay got. They might have something on their website.

I think DeWitts are probably the best but there might be some good info on this site.