04-28-2006, 09:49 PM
haha, I don't know how cool it is-- more of a curiosity? And maybe only to me and you. I can't imagine most people care! :lol:
Upon further testing today and yesterday, the gauge definatly isn't QUITE the super duper replacement for a temp gauge that I hoped it would be, but I still like it. What I was wondering about before is true.
The operating pressure IS determined by the temperature of the coolant when I start the car. Like I noted before, with ambient temps of 60-70F, once my car is up to temp, the pressure is ~7 PSI. To simulate the "hot day" situation, I let the car warm up for just a minute or two, just a little pressure had built. I opened the radiator cap, head temp was 140, water in the rad was 130, a little hotter than I meant to go, but that's ok. Now with the cap back on, and pressure at 0 again, once I went on down the road and reached normal temp (175ish), my new operating pressure was only 3 PSI. I expect that in the winter, with sub zero starting temps, I'll see normal operating pressure quite a bit higher than 7 PSI.
So that was kind of expected, oh well. The gauge will still follow the temp gauge in movement, but you can't say that 7PSI = 175F. I'll just have to note the "normal" pressure once up to temp, and if I were to lose my temp gauge, the pressure gauge can still act like a backup as long as I knew where "normal" was. So not too bad.
An interesting side note/thought. If you were at the track, and opened your cooling system to check the level or something while it was fairly warm, when you close it back up, your operating pressure is going to be lower. Which gives you less protection from overheating. :!:
Just for kicks today, when I got home I left the car idling and didn't turn on the fan. Put my temp probe on the head.... I chickened out at 225F, but as expected, the pressure gauge hit about 18 PSI sometime around 215F and didn't go any higher. At least I know it's working!
Umm.... that's all. Oh yeah, I took out my gauge cluster, cleaned and retightened the grounding nut on the back of the temp gauge. And also did this to bypass the stupid, non-functioning SI batteries. Picture and idea stolen from E30tech:
![[Image: DSC01554.jpg]](http://sumdumguy.com/tom/DSC01554.jpg)
just in case any of you other few E30 people have the same problem, either one or both of these things brought back my temp gauge. Works better than ever. :wink:
Upon further testing today and yesterday, the gauge definatly isn't QUITE the super duper replacement for a temp gauge that I hoped it would be, but I still like it. What I was wondering about before is true.
The operating pressure IS determined by the temperature of the coolant when I start the car. Like I noted before, with ambient temps of 60-70F, once my car is up to temp, the pressure is ~7 PSI. To simulate the "hot day" situation, I let the car warm up for just a minute or two, just a little pressure had built. I opened the radiator cap, head temp was 140, water in the rad was 130, a little hotter than I meant to go, but that's ok. Now with the cap back on, and pressure at 0 again, once I went on down the road and reached normal temp (175ish), my new operating pressure was only 3 PSI. I expect that in the winter, with sub zero starting temps, I'll see normal operating pressure quite a bit higher than 7 PSI.
So that was kind of expected, oh well. The gauge will still follow the temp gauge in movement, but you can't say that 7PSI = 175F. I'll just have to note the "normal" pressure once up to temp, and if I were to lose my temp gauge, the pressure gauge can still act like a backup as long as I knew where "normal" was. So not too bad.
An interesting side note/thought. If you were at the track, and opened your cooling system to check the level or something while it was fairly warm, when you close it back up, your operating pressure is going to be lower. Which gives you less protection from overheating. :!:
Just for kicks today, when I got home I left the car idling and didn't turn on the fan. Put my temp probe on the head.... I chickened out at 225F, but as expected, the pressure gauge hit about 18 PSI sometime around 215F and didn't go any higher. At least I know it's working!
Umm.... that's all. Oh yeah, I took out my gauge cluster, cleaned and retightened the grounding nut on the back of the temp gauge. And also did this to bypass the stupid, non-functioning SI batteries. Picture and idea stolen from E30tech:
just in case any of you other few E30 people have the same problem, either one or both of these things brought back my temp gauge. Works better than ever. :wink:
The only thing that stops a bad guy with a van is a good guy with a van