Benefit of 180* tstat?

RysRed96GT said:

whats the benefit of having the engine run cooler? i always thought engines didnt run as efficiantly when cooler than normal

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The advantages of the cooler t-stat are:
plastic parts last longer...
thicker oil, more oil hanging on the engine from the
last time it was used.
Note, you can turn the engine fan on by turning the
air knob full CW.
.
The advantages of the hotter t-stat are:
thinner oil, help Ford's cafe situation by improving the
number in the mileage test by .032 mpg.

Cooler engines areless prone to detonation.

Hotter engines wear less (Less wear between aluminum pistons and iron cylinder walls)
Hotter engines promote better and cleaner combustion (Fewer carbon and ash deposits, better mileage)

Riley

Note, you can turn the engine fan on by turning the air knob full CW

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What is full cw?

Josh

clockwise, to defrost or a/c

>Cooler engines areless prone to detonation.<
I dissagree. Detonation is a function of spark timing,
a/f, charge temp, VE,, detonation should be controlled
by the ecm.
.
>Hotter engines wear less (Less wear between aluminum pistons and iron cylinder walls)<
How do you know this?, IMO, the issue is whether the
piston rings are properly lubricated.
.
>Hotter engines promote better and cleaner combustion (Fewer carbon and ash deposits, better mileage)<
With a car that never gets fully warmed-up, maybe,
with the car warmed up, and in closed loop, don't think so.

Rio96 said:

I dissagree. Detonation is a function of spark timing,
a/f, charge temp, VE,, detonation should be controlled
by the ecm.

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Yes, spark timing is a contributor of detonation, but heat is as well. The less heat you have in the engine, the less chance you have of your fuel spontaneously igniting (detonation).

You say that charge temperature is a function of detonation. What do you think happens to the air when it enters the combustion chanber? It's gonna start pulling heat from the cylinder walls to match it's temperature with that of the engine. If your engine is running cool then there is less heat to be transferred from the chamber to the charge.

Rio96 said:

How do you know this?, IMO, the issue is whether the
piston rings are properly lubricated.

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Yes, lubrication plays an important part of the wear process, but temperature does as well.

"The coefficient of friction between aluminum (pistons) and iron (block) is a function of temperature. As the material's temperature increases, the coefficient of friction between the materials decreases. There is a sharp inflection in the curve of this property between 170-180, where the friction will increase rapidly with temperatures below 170."
-Mechanics of Materials, 5th ed. Dr. Jack McCormac, et al

Rio96 said:

With a car that never gets fully warmed-up, maybe,
with the car warmed up, and in closed loop, don't think so.

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The more heat you have inside the comustion chamber WITHOUT causing detonation gives you a more complete burn of the A/F mixture. Having a more complete burn gives you more power, better mileage, and fewer hydrocarbons (emissions).

This is why auto manufacturere have been steadily increasing engine temperatures in the last few years.

Riley

"Yes, lubrication plays an important part of the wear process, but temperature does as well.

"The coefficient of friction between aluminum (pistons) and iron (block) is a function of temperature. As the material's temperature increases, the coefficient of friction between the materials decreases. There is a sharp inflection in the curve of this property between 170-180, where the friction will increase rapidly with temperatures below 170."
-Mechanics of Materials, 5th ed. Dr. Jack McCormac, et al"

nice find but getting a 180 degree thermostat doesn't mean the the metals are at 180* I am sure they are much higher than that.

redlined50 said:

nice find but getting a 180 degree thermostat doesn't mean the the metals are at 180* I am sure they are much higher than that.

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Your absolutely correct. The temperature in the metals are probably higher, but I was trying to point out that running cooler isn't always better.

Some people have that notion inside their head and will go out to the part store and find a 160* or even a 150* thermostat because they have overheating problems. Most of the time, a cooler stat is just compensating from a clogged rad or failing pump.

Now, with a 150* stat, I'm willing to bet that they are causing much more wear than if they have a stock stat.

Just my $0.02

Riley