OK, let me word it this way since it appears the point of the question was completely missed.

This was posted in this thread.

So, the oil has to normally be 200*F to achieve 200,000 miles?

Or will the engine be fine and reach 200,000 miles even if driven on shorter runs so the oil seldom reaches 200*F as long as you you follow the OLM and perform oil changes?

And finally, what's the difference from the second question on a stock engine vs using a 160*F thermostat that runs the engine and (presumably) the oil a little cooler?

This is basic stuff to answer. It doesn't require anyone throwing a fit and being insulting.

 

The 200,000 mile engine life is obtainable on a stock engine that's regularly used and maintained following GM's engine oil spec and recommended maintenance schedule.

If you modify the engine, do not use the vehicle/engine as designed, abuse the engine or do not follow the maintenance schedule; Expect a shorter engine life.

One may think a slight difference in engine coolant/oil temp (160* stat vs stock stat) may not have much of a negative effect on the engine, its wear and longevity. But remember, the temperature on the gauge is a reading of fluid temperature at the sensor. As ET stated, even slightly cooler engine oil may get trapped in areas.

Now I'm only speaking in a general. There are many factors that come to play, more specifically driving habits. If you take a guy/gal that hops in their car and romps on the gas at every street light, I think the engine abuse alone will cause engine failure faster than any other factor (160* stat).

I think a big issue is that most Corvettes are not used as designed/regularly, making the impact of the 160* thermostat greater.
The main thing is these engines, the oil and cooling system are designed to work together with engine longevity in mind. Once you modify these, you shorten the engine's expected life, they are no longer working in harmony.

We're lucky the LSx engines are designed so well and durable, try putting a 160* thermostat in some of the other engines out there (GM's 3.6L or 1.8L), and we thought we are having oil issues now

 

I's like to know WHY people with little or no background in any of the engineering disciplines that go into designing a car seem to know better than people who have the credentials!

 

Oh so you think they have credentials just because they say so on the internet?

most of use change the oil well before the OLM says so.. the OLM goes partly by engine temp no matter what it is, so the algorithm should adjust. But, after you start modding a car, all bets are out the window anyway. And No, a 15-20 degree difference in COOLANT temp will not hurt only help with power. Oil temps are still 190-200 on a cool day, the same as stock - maybe 5 degrees cooler watch out!

 

n8dogg, you gave a nice answer but it did not address my question.

If the OLM compensates for the colder oil temp for the first 10 or 15 minutes of driving until the oil warms up and still allows a 200k mile engine life then why can't it compensate for the colder oil temp due to a cooler thermostat and still allows a 200k mile engine life?

If the OLM compensates for the colder oil temp when the car is driven in -40*c conditions and still allows a 200k mile engine life then why can't it compensate for the colder oil temp due to a cooler thermostat and still allows a 200k mile engine life?


I'd like to know why people think posting questions is "knowing better"?

 

How about adding a block heater to the engine for those who mod their cars for more power or who only drive their cars for short periods or in cold weather?

When I had a block heater in my 88 Gran Prix it was already warm when I started it in the cold winter and only took a minute to reach regular operating temperature.

 

You may want to go back and re-read. The 200k mile engine life does not solely rely on the OLM.

A block heater is only helpful when initially starting a cold engine. If you're looking for slightly higher engine temperature, then why not go to a 180* thermostat.

 

Maybe I will depending on what the engine temperature is during my typical driving.
I had the SC installed at the end of September and only drove the car for 6 weeks before I put it away for the winter to do my other projects.
If I go 180 and get any pinging I can always go back to the 160 or drill a 3/16 hole in the 180 and see how that goes.
It won't be until March or April since I'm not driving it until then.
It seems to warm up to operating temperature within 5 minutes.
I'm not that hung up on engine life since my car only has 25,000 miles
and it would take me 7.5 years @ 10,000 miles per year to get to 100,000 miles which is the half life based on the info in this thread.
I didn't do all this modding it to 600 hp to drive it like an appliance

 

Fine, following the OLM and actually changing the oil with the correct oil when it tells you to then as well as following any other service recommendation in the manual. Is that better?



It was pointed out rather rudely how the OLM does all these fancy calculations and compensates for the cold starts and different operation conditions. So, the question still stands - why can't it compensate for the changes due to a cooler thermostat?

The calculation code should be monitoring coolant and oil temperature so the logic which derates the oil life should just de-rate the oil life quicker with the cooler thermostat. Follow the monitor and change the oil and voila you still get the same engine life. So, again, why would the 160*F thermostat used during nice "Corvette weather" days be any different then driving the car with the stock thermostat in say -30*C temperatures?

 

In your case I wouldn't be too concerned about the thermostat. The heat generated from your supercharger is a much greater threat than a lower temperature thermostat. You're right in determining what temperature your engine runs at before making a decision to make a change.

This has all been covered in this thread. If you can't understand that, I'd recommend leaving your car alone and follow the advice of your local Chevrolet dealer.

 

I'm getting really sick of people who respond with backhand passive insulting comments. It's sad when so many people use that as the way to get around the forum rules of attacking other people....

All I asked were some questions. I don't need to be reading insulting crap in ever other response I read.

 

If you feel like you're get insulting responses in other threads as well, you may want to look at the situation from an outside point of view, it may surprise you.

200k miles is obtainable on a completely unmodified engine, that's driven regularly, not abused, and maintained following GM's recommendations. The OLM is not the only reason why you can see 200k mi. The OLM, oil type, fluid temperatures, and engine design all play a role in a durable engine. The fact that something was changed (stat) is what impacts the life expectancy of the engine, not whether or not the OLM can compensate (the OLM is a guide!).

Here's a completely unrelated example to help illustrate this.
Baking a cake: In baking, the perfect mixture of ingredients and oven temperature will either make or break a cake. If one of the ingredients or the temperature of the oven is off, even the slightest bit, it can ruin the cake.

 

OK, try this. What is the minimum ambient temperate a stock C5 can operate in and still obtain a 200k mile engine life expectancy? Call your answer X*C.

Now, is operating the stock C5 at X*C more severe on the engine then operating the 160*F thermostat C5 at Y*C, where Y*C is greater then X*C?

For example, say the C5 can be operated in -20*C weather without affecting the expected engine life. Is the operation of the stock C5 at -20*C harder on the engine then the operation of a 160*F thermostat equipped C5 at >=20*C weather?

There really is no answer. In real life no two people use the car the same way. But, when you're using your 160*F thermostat equipped C5 convertible for nice sunny warm weather top down cruises should you really be worrying about any extra damage to the engine that thermostat ~could~ be causing?