Interesting...

One mag's take on ideal temp for power, vs. ideal temp for motor life. Dyno numbers too.

Bottom three pages... Fan Control, Corvette Fever, June 1999

I've always been lead to believe low coolant temps are not good for your oil... but I've talked to a lot of people on boards who don't consider it to be much of a problem.

I'm still considering doing a 160 t-stat mod for the summer here, but simply putting in a toggle switch to my DC fan controller to toggle turn-on temps like this VHP controller. I'm just not sure how efficient the front grille and the radiator are at cooling things on their own, at speed. The trucks sure don't have constricted radiator ventilation like the vettes.

 

"The problem is that if you regularly drive your Corvette that way [between 160*-175*], you are going to wear out a lot of parts. The first thing that goes is usually the catalytic converter. Then you're going to need an oil change every 1,000 miles if you constantly run your engine below 200 degrees. The oil will never get hot enough to rid itself of moisture and contaminants".

--well who cares about catalytic converters

--The second part is very interesting to me. I am assuming 'moisture' is simply H2O which would only boil off at +220*F This makes sense. I wish they went further into detail about how oil can self rid contaminants through an increase in temperature. (but I am sure most readers don't care to look at it in that much detail -which I can't blame them. I'm just curious)

But look at those increases in torque and horsepower with low coolant temps That is like putting on headers almost.

Good find marc_w

 

any oil - any....
is hydroscopic
which means it has the ability to absorb moisture.
we change our oil because it gets contaminated - it doesnt wear out.
Oil and engine manufacturers do rec a certain engine temp - which does allow some oil contaminates to be burned off - I am not an oil chemist but
most folks will agree that the min coolant temp is 160F for this to occur
I will look thru some of my ASE books for some more info

I do disagree with the wearing out parts statement. Silly
Cooler under hood temps have proven longer part life.
Cat wearing out.??? Exhaust temps not coolant temps effective cat convertors
Coolant temps will cool combustion temps to point where the effect Cats ?
little common sense here.
oil change every 1k miles. silly
My 1991 Silverado has a 180 F in it - bought it with 6k miles in 91
always used Mobil 1
Changed every 3k or 3 months
Never had a problem after 125k miles
I have 2 other big block vehs with 160 F in them - never a problem
The 03 truck and another car have 180 F in them - never a problem

Cooler TStats are a good thing to a point

 

Well, I have not actual experience in this area, but I have to say cooler temps do not provide longer (internal) part life. If you don't let your engine heat up to proper temps , all of the internals and bearings haven't properly expanded which could mean uneven wear. If you were at high RPMs with 160 degrees temp, this could cause problems such as crank walk, etc in the future. I'm not basing this on fact, just opinion.
Philip S.

 

Philip,
Possible...
But also remember - engines have a tolerance.
I think there is also a major difference between coolant temp, actual engine temp, meaning head, clyinder temp, and exhaust gas temp.
I feel by making a blanket statement that lower coolant temps below 200 F will wear out parts in or on an engine is a unfounded and silly statement.
My .02

 

Doesn't using a 160* Thermostat allow a tad more timing and prevent detonation? Heat kills engines, not cooler coolant. That's stupid. I say, where's the proof? I'm talking about the article, not anyone on this thread

 

not a an expert on metallurgy but I know that the GM engineers elimenated the piston skirts on the gen III motors 4.8,5.3,6.0, ls1, ls6. They did this to lower rotating mass. The last time we had several GM engineers here (to argue with us as to what was wrong with the vehicle) we had a pretty heated debate on this due to the complaints we have from customers in the service dept. about piston slap in the early morning. They state " due to the short time the vehicle experiences this we have seen no damage to internal component wear, due to the fact that the engine only runs cool for a brief time until the cylinder temp. reach a high enough temp. allowing the top of the piston to properly expand " . I then asked them about several aftermarket mods that are said to improve performance (tb bypass, colder stat, cold air induction, electric fans, ect.") & why they did not engineer this into the vehicle. They then began to explain things such as optimum temps for prevention of oil degradation, component wear, metal expansion, molar mass of air & so forth. They also stated that all of these parameters are factored into the design & programming of the vehicle & they have done endlees hours R&D to optimize for fuel economy, emission's, & reliability. They felt that changing any of these factors would be detrimental to reliability. Another weird thing as well I thought that I would one up them so when we got back I showed them LS1 edit. They laughed at me & explained that there are 8 tables in a GM program & we are only viewing 7 of them & not all factors of the 7 tables. Maybe this is why our **** is always breaking. It seems that an unmodified stock vehicle can be beat to death with our fleet customers But the second one of us starting modding things start breaking even without deleting torque management. I do not care though I say screw them, I will just keep buying new, fix them up, break em', & then let warranty fix em'......lol...

 

I also feel that they engineer these cars/trucks for the masses
few are designed with us and modifications in mind
How many trucks they make a year ?
How many trucks are modified by folks like us ?
The percent has to be really small.

They take into account altitude, temps from texas to Minn, and everything inbetween to come up with an all around liveable and reliable veh.
I feel they take liveablitity and reliability first - emissions second - and performance third, only if one and two can be satisfied.

but the mods we do, work - we increase power and many times MPG

 

The bottom line is, what Crazy cutter basically said. If engines with 160 thermostats ran better, gave more power, and increased reliability, why don't mass produced engine's have them, this goes for most "Bolt on" parts as well.
Philip S.

 

$$$$ that's why