Motor Temp Equilibrium Point-Cooling Question

[ubtripn]

I have been working quite a bit on my 68 with a new crate engine trying to achieve one thing - NEVER HAVING TO BABYSIT THE TEMP GAUGE. I have a new 4 row rad/clutch fan, shroud and t-stat.

First - I was running too hot with a 180 stat when it is over 90 out here.

Second - I removed the stat to see what the engine would naturally level out at. It works it's way up to 170 and is consistent unless I am sitting in traffic and it is hot out.

Third - I put a 160 stat in that opens around 170 and holds it there unless I am stopped for 10 minutes or so while 90 or greater out. If it is above 90 I run a consistent 180 when moving. We are going to hit above 100 this week.

I put the stat in so it would warm up quicker. I also didn't want to sin and not be boiling off these vapers and sludge that I have heard about. I also put a pusher fan on to augment the system for sitting in traffic - comes on at 185 and shuts off at 170. It is connected between 6 and 8.

I think I have found the balance but I do not want to wear the engine out prematurely. It is not injected nor does it have vortec heads. Shouldn't averaging 170 be ok for my engine life?

(I should have started with checking the accuracy of the temp gauge. Laser on t-stat housing reads 20 degrees cooler. I still don't know which to believe, my mechanical in the block or the coolant temp at the housing.)

[davepl]

The coolant will continue to accumulate heat so that thermostat housing should be the hottest part of the system, I think.

If you can control the temp down to 170-180 while moving, then your radiator and system is likely of sufficient size.

You may never get it to run cool at idle, though my LS3 still does.

You definitely want a t-stat, probably around 180. If it gets hotter, who cares. As long as it can control itself and stay under 230 at extended idle on a hot day in traffic, that's all you really care.

Ignore any weirdness about T-Stats creating a restriction so that the water has more time to do its job and so on, but you do need one for proper warmup.

[ubtripn]

So my 160 stat causing me to balance around 170 is safe for my engine?

[davepl]

Originally Posted by ubtripn

So my 160 stat causing me to balance around 170 is safe for my engine?

Oh heck yeah. Modern cars run around 210 by choice, so you've got a BIG safety margin. Presuming it can hold it in stop and go traffic, of course.

If it were me I'd run at least a 180F in summer, 195F in winter. Colder engine just creates more wear and tear, really.

[Valarius_Starchaser]

the term hot to an engine means 220. 170 is cold and is overkill get minimum a 180 the oil will be more viscous and lubricate better don't fix a problem that isn't there and make a problem in the process

[ubtripn]

Good advice, thank you.

[tdangle]

I have always heard as long as the engine is running between 180 and 200 your good.

[Larry Weaver]

Had a problem with my 67 camaro running hot in traffic even with a new rad ect. I took the thermostat and put 4 1/8 holes on the outside but far enough in so it will let water flow all the time. You can not take thermostat totally out because water will flow to fast to cool.Cheap and it helped a lot!

[ubtripn]

Sounds good, thank you!