Thermostat

It's not. Why do you think that? Running a too-cool thermostat is bad for the oil, bad for the fuel management system, etc.

CJ

Unless you have had you PCM reprogrammed, a 160 degree stat would be a horrible idea. The computer will constantly run in closed loop at 160.

I believe the idea is that you run a modified computer 'chip' in your car that boosts power, and part of that is you are required to put in a cooler thermostat so the management thinks you are running cooler and therefore will supply more gas.

In general, it is not a good idea, your engine is supposed to (engineered to) run at 190 (ish) for optimum efficiency and durability. People incorrectly believe that their overheating prone engine can be cured by putting in a cooler thermo, but think about it, it doesn't matter if the thermo opens at 160 or 190, the engine will still keep heating up to overheating if it has a problem, just a little slower.

Common causes of overheating engines can be by low coolant (mix), stuck closed thermostat, clogged radiators or coolant engine passages (inside) or clogged rads on the outside (clean all those bugs and leaves off), cooling fan not working (electric or clutch or missing blades), incorrect timing, other components dragging the engine down. Also low oil level or really old oil can contribute, but your engine would probably also seize.

Hrm. I wonder what the rules are here.

My '90 C1500 350 had a 190 degree T-stat, but the GM crate motor I swapped came with a 160 installed by GM.

Since I have an OEM prom, should I switch to a 190 degree?

My 1971 Corvette has a 160 too, but there's no tellin' how many times (and former owners) have swapped it out.

-Steve

Actually a low concentration of "coolant" shouldn't cause overheating. Straight water actually cools better than the majority of antifreeze products out there. Problem with running straight water is rust, in particular with cast iron block and or heads. The term "coolant" is actually a misrepresentation of what the product is. The product is primarily for raising the boiling point of the water, inhibiting corrosion, and significantly lowering the freezing point of water.

The one in the crate motor should be changed to a 190 if running stock EPROM. The one in the vette should be fine, assuming the carb has been tuned for the lower operating temperature.

Excellent answers, thank you all. I am getting ready to change my rad hoses and that is great time to change the T-stat but guess I don't need to. Mike

??? You MUST use the 190. I thought you still had the 160 in it.

It is still bone stock. I am changing the rad hoses for the first time on this truck. Mike

With how hard it is to change out the t-stat, and the fact that you are already messing around with the coolant system why not do it. Not talking much money at all, you have the labor in it already, and this is just cheap insurance. After all, its better to do the mantinence then the repairs.

just a couple of rants. Oh, i have one question, has anyone ever seen a t-stat go dead in the open position?

Mike Copeland wrote in news:3fbce744 snipped-for-privacy@news1.prserv.net:

"> Oh, i have one question, has anyone ever seen a

Yes.

If it aint broke..... Mike

: :makes the motor stay in 'warm up' mode...

: >

: > Unless you have had you PCM reprogrammed, a 160 degree stat would be a : > horrible idea. The computer will constantly run in closed loop at 160. : : Hrm. I wonder what the rules are here. : : My '90 C1500 350 had a 190 degree T-stat, but the GM crate motor I swapped : came with a 160 installed by GM. : : Since I have an OEM prom, should I switch to a 190 degree? : : My 1971 Corvette has a 160 too, but there's no tellin' how many times (and : former owners) have swapped it out. : you 71 vette didn't have a puter controlling the system...

"quakeholio" wrote

In my experience, that's the most common failure mode.

Ian