Question: What is the correct "real" operating temp for a 1970 small block.

[Bolisk]

My corvette's temp gague has always read low. . .like 110 when fully warmed up. I've replaced the temp sending unit (with a Lectric Limited correct one), the thermostat, radiator, and water pump.

This low reading has always bothered me. So I took it to a vette shop to see if they could look at it. They said the cars temp is fine, and the gauge is low. . .and not two worry about it.

Well. . .I tried not to worry about it for over a year. . .and was successful. Until x-mas when my wife bought me a IR temp gun. So today. . .it reached nearly 70 degress in the chicago area. . .and I took my vette to work. On the way home. . .it was warm enough for the engine to get up to it's normal gauge temp reading of 110.

The moment I pulled into the garage, I left the car running, open the hood, grabed my IR gun and took a reading off the thermostat housing. The gauge read 220!!!! The hose about 1 inch away read about 190.

Is my car running hot? Or is 220 acceptible?

-Bolisk

 

[Bolisk]

Oh and if anyone knows how to get my temp gague to read right PLEASE give me suggestions.

thanks,

-JR

 

[Copdogcorvettes]

Oh and if anyone knows how to get my temp gague to read right PLEASE give me suggestions.

thanks,

-JR

Just a guess, but maybe someone along the way has removed the needle and put it back on in the wrong location. The the needle go below the lowest marking on the guage went power is off? To fix it remove the guage; note the needle location before you remove it. Then remove the needle and replace it in about what you think is about the right location. reinstall and see where it reads.
As for proper temp; that depends on the themostat 180 - 195. SBC run their best at around 190 degrees; SB fords (I know that's a dirty word) run best around 145.

Gary

SAVE the WAVE

 

[Rebelrob]

Yep, your car guage is wrong. Does not run that cool. 70 degrees out is cool temps. With AC turned off depending on your thermostat, probably should read between 160-190. I think the smog motors were designed to run hotter just for emissions standards, which is what I have at the moment. My SBC 350 I had in a 79 camaro had a 160 thermostat with a flex fan. That fan could pull some air let me tell ya.
This is the truth, I could have the hood open and sitting in the car revin the engine and stick my head outside the corner by the windshield and it would blow my hat off when I ran it up to 4 or 5K on the tach. If its running hot, may want to try different thermostat or new fan or some electric fans also. Definately the guage needs attention.

 

[JohnZ]

The moment I pulled into the garage, I left the car running, open the hood, grabed my IR gun and took a reading off the thermostat housing. The gauge read 220!!!! The hose about 1 inch away read about 190.

Is my car running hot? Or is 220 acceptible?

-Bolisk

An I.R. gun reading at the thermostat housing will always be high, due to the glossy surface; the correct "shot" is from the hose, just above the housing, which is a matte surface. 190* is fine.

 

[TMPJoe]

the only fix for that bad temp gauge is another one...

so much fun working on the guages