My temperature gauge(stock) never reads above 160 degrees and I am questioning it's accuracy. What's the best method to get an accurate temperature of the water in my engine so I can determine if the gauge is accurate. If the gauge is correct, am I running too cold or is 160 fine? I've got a 180 degree thermostat.

Thank You

The cooler the better.

Frank,
Are you the real Frank Rizzo? I've got this Jerky Boys tape at home where these guys make prank telephone calls to people and use "Frank Rizzo" as the identity of the caller. Funny as all get out!

So I shouldn't be concerned about running "too cool"? However, I should check the accuracy of the gauge I guess so I would know if things were overheating!

If the engine is too cool, then you get a buildup of condensation in the oil, which is not good. Sometimes fuel economy will suffer a bit from low coolant temperatures as will hydrocarbon emissions.

Scott,Kooler is only better to a point. I have read in mult publications by very well noted engine builders like smokieYunick,Lingenfelter,Grumpy Jenkans,etc that the sweet spot temp for the most power & efficiency is approx 180-190 deg f. I have also seen the same results on dyno testing done to answer this very question in hotrod & super chevy over the yrs too.If you running 160 it's too cool IMHO.

Where is your temp sending unit,in the head by the ex port or in the intake where it can read lower?

If it's in the head i would suspect a bad sending unit or gauge.

If it's in the intake i would get one of those thermometers that the automotive AC guys use that go up to 220 deg f for a test. Then with the motor cold pop the rad cap off and then twist it back on untill it hits & goes over the 1st click where it stays on but is not really snugged down tight yet to hold much pressure. Then warm it up either in the driveway or take for a ride then let it sit for a good 10 mins and then carefull remove the cap. (The cap should have little to no presure on it because you should have left it loose from before you started the car as mentioned above/but still be-carefull anyway) Then just place the metal probe end of the AC thermometer into the coolent through rad cap opening(let stabalize a min or two) to get a much closer/more realistic idea of what the actual coolent temp is.

I did this with my car and when my brand new autometer mech temp gauge read 210 deg f in the car the coolent read 190 deg f through the rad cap opening. I also slipped it inbetween a couple fins in the rad to touch 1 of the tubes and the delta between the gauge and thermometer stayed approx the same @ 18 ish deg f more at the gauge than the actuall coolent temp. I did a calib check on the ac therm i had and water boiled at 213deg f(1 deg off) and it matched an outside therm @ 90 deg f that day so i know it's reading decent /correctly.

Try this and let us know how you make out.

Scott

What is "too cool" a temperature?

Scott,
Your post popped up as mine was being entered so you answered my question already as I was hitting "enter". The sender is in the head and my uncles do residential heating/cooling and I've seen them use one of those thermometers you're talking about. I'll get one and do as you instructed. Will keep you posted. Thanks a lot. You're always a "wealth of info" for me.

There is a reason you cannot purchase a thermostat for a GM gasoline engine with a temp. lower then 160*F

I can only speak about MY car on this ... Track only car also .. leaving the line at 140* the engine would " burp " atleast once at the hit, leaving at 160 .. it didnt miss a lick but MPH and ET would drop a bit ... leaving at 180 was what it liked the best.

Years ago I had a Pontiac Bonneville that ran between 140-145 w/ 2 differant gauges and it ran fine for what it was ... never had it apart to see what the insides looked like.

I was always told heat makes HP. I know on the alcohol dragster I worked on, the barrel valve adjustment was critical as far as heat in the motor. We tried to launch around 180. If it left higher you usually had tire shake problems.

Your gauge or sending unit has to be off if it's in the head, or you've got the wrong color resistor on the back of your temp gauge.

Quick test: boil water in the microwave in a pyrex measuring cup or similar. In the time it takes you to get from the kitchen to the garage, the boiling water won't lose that much heat - stick the sending unit in and see what your gauge reads. If it's still at 140° you'll know it's off.

My guess is you have the wrong color ceramic resistor (if you're using a stock type gauge) or need a different sending unit if you've got aftermarket gauges.

Sorry, I couldn't resist - here's your link:
http://www.chevelles.com/cgi-bin/forum/ultimatebb.cgi/topic/22/863.html?#000000