Replacing my leaky 23 year old radiator with a brand new one (thanks schwank) and thought I would pick up some new upper & lower mounts and a new thermo switch, come to find out there are 3 temp levels of these switches (75/82) (85/93) & 95/102) Which one would be recommended living in Southern California. I drive the car like it shouild be and have participated in a few DE's and plan to do more this summer.
Thanks in advance for your suggestions.

 

Any thoughts?

 

You don't mix temperature ranges of termofan switches and thermostats. You need to match them.

Take, for example, you put a 75/82 thermofan switch in, with an 85/93 thermostat. Your fans will be running all the time, or at least coming on and off regularly. Go in the other direction, and your fans turn on too late.

If your fans turn on and off at the proper times now, replace your thermofan switch with the same temp range that you currently have. If not, get in there and replace/inspect the thermostat and match it to a thermofan switch.

 

I have always run the lower temp. units in my 944's. The temperature seems to stay much more consistent at the quarter mark on the gauge.

 

Use the 85/93. My switch went bad two weeks ago and i replaced it with the stock heat range which is 95/102 which is what i thought i originally had on the car. Turns out i had the 85/93. I am seeing higher water temps on my digital gauge than i would like sitting in traffic (goes from 160*F ish cruising on the highway up to 208*F or so before the fans kick on with temps in the 60's ambient). Basically on the stock gauge that is the first white line to just under the 2nd white line. With the 85/93 the fans would kick on about 185*F and would never go past the halfway mark on the stock gauge.

I am replacing with a new 85/93 switch whenever the UPS guy gets here..

BTW, i did a track day this past weekend with the 95/102 switch. I saw no difference in on track temperatures really.. temps hovered right around the 1/2 mark or about 185*F in mid 60's ambient. Your really going to see the difference when sitting in traffic, like on my trip home i recorded my highest water temp to date, 211*F sitting in an hours worth of traffic in Manhattan. With the 85/93 it probably would have barely went over 200*F.

 

Techno Duck, thanks for the info...so just to clarify, I think you're saying that it's OK to run say a lower temp thermo switch than the thermostat in the water pump?
The thermostats come in 71 , 80 & 87 degrees
while the thermo switches are available in 75, 85-93 & 92-102. So I'm assuming if you're running a 80 degree thermostat, you should run an 85-93 thermo switch? or can you run a 75 degree?

 

In my opinion you match them 71 with a 75, 80 with an 85-93, etc. That's how they were matched when the car was built.

I didn't mean to imply by my earlier post that putting a cooler thermofan switch in is going to make the car not run properly. It will even make it run cooler, as the fans will come on earlier. But they will come on almost ALL THE TIME, and they will likely stay on. If you want to drop your thermostat temp as well, I don't see why you couldn't use the cooler thermofan switch now, and then change your t-stat later as long as you're willing to deal with the fans being so much until you get to the t-stat. That's what I ended up doing, and it worked out fine, but I found it annoying enough that I went back in and changed the t-stat a couple weeks later.

 

Thanks Daryl, that's kinda what I thought. Ordered the 85-93 to go with my 80 degree t-stat. Long way around to a simple solution.