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Blacktank

chevy 305 4x4

it starts off with everything working fine running 190ish but had stock housing with extra not being used censors so i got a new housing and thermostat,well the thing would stick on first warm up,go up to 230-240 before it would open,replace thermostat,well this one does the same thing,replace thermostat,new design different maker,works but the running temp are just above 210 when it opens and then just below 210 so must be a 195 thermostat and not 180,i had a look and oem is 195

so what is everyone's preferred running temps,i will be replacing again for a 180 thermostat,210 is just cutting it to close for my liking
The hotter the better.
Every aspect improves- efficiency, power and engine longevity.

However, something doesn't sound right.
Temps are far above the T-stat range- and that's not normal unless it were under load.
Is the radiator plugged? Fans not turning on or fan cowling missing?
my first though was an undersized or blocked radiator. How is temperature being measured? is the gauge accurate, any way to confirm?

If the particular engine has computer controls, and is expecting a 195f thermostat and you put in a 180, then say good bye to about 15% of your MPG's if the radiator actually has the extra capacity to reduce the actual temps, which it seems like it does not.

Blacktank

rad is fine 3 core aluminium,will check the pump flow next time it is warm

the old thermostat must of been 180 and the new 195,so the temp are right where a 195 would be,maybe it's just me being old and wanting to keep below boiling? but it a 60 degree day so on a 90 degree day i could expect 215-220 so will go back to 180 and see what happens

1985,no computer and emissions long gone,hei and edelbrock carb
The boil point goes up if you have antifreeze in it............better combustion at 195* ?

Huh

Blacktank

my factory gauge has 210 at the center and that where it's at so maybe thats where it supposed to be at and it's that for the last decade i have had a 180 in and used to seeing it 15-20 degrees cooler?

did a quick google search and brought up a bunch of forums with who knows who saying whatever,will try to get something legit

yea,the guy who runs a forum doest trust info on forums,it aint right
Definitely.

Heat helps fuel combust. Why it's hard to get a car to start when it's -20°F
It's more efficient, as less heat is transferred to hotter cylinder walls/head. (There is power in having the charge cooler, but not the engine, per se)
And fuel has less tendency to condense on hotter cylinder wall and wash off oil-
They didn't realize this until the '30s, then, with hotter engines they lasted lots longer.

Most people naturally think cooler is better, but that's wrong.

I worked at an auto machine shop- For example, Boring a six, where the cold coolant came in from radiator and hit #1 cylinder it would wear and need largest oversize,  the rest of the cylinders would've gotten by on smallest oversize bore.

For GM you're lucky, they actually make a 205° stat as an option. I've turned them down to fit my application.
I have a 180 in my 1986 g20. Runs 180 in the spring and summer and 190ish in the heat of the summer. In the winter I use a piece of cardboard with a square missing in the middle, in front of the radiator. Runs 180 or so then. The cooler thermostat might hurt the mileage ever so slightly but helps a bit with the power. Every little bit helps as a 305 isn't known for its power, even with my L69 which is a truck version of the 305HO.

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I used some thermal epoxy to adhere a K type thermocouple to the thermostat housing, as my stock dash gauge started acting differently.

Basically the hottest the K type thermocouple got was 207f climbing the grapevine, while dash gauge showed not much higher than normal. Other times when dash gauge read much higher than normal, K type registered 196.5f.

So basically I take my dash gauge reading with a huge grain of salt and only worry if its readings are well outside what i have determined to be 'normal.

I also have an IR temp gun and it largely agrees with my K type thermocouples, which I will put nearly anywhere temporarily or more permanently with arctic silver thermal epoxy.

I never trust one abby normal gauge reading or make mechanical decisions based without confirmation. Well, not anymore anyway.
Only thing I’ll, add is that with an old 1982 GMC 22’ class C with a 400 Chev and a partially plugged 3 core factory radiator, I dropped $400 and got a new 4 core installed, then it actually improved gas mileage from 7 mpg tp 9. I think it was a 195 t-stat.

I felt a lot better about climbing grades with the a/c on, which I never could do before. Usually I was on the side of the road with the hood up waiting for it to cool down...

But that was back in the 1990’s up in Penticton BC...