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JFP in PA · 07-12-2009, 08:14 AM

OK, let's put this one to bed: The LN thermostat will lower the point at which the coolant flow starts by about ~25 F. Considering that the dash gauge is inaccurate as Hell (when it reads between the "8" and "0" on the "180", the car is actually at about 205-210F), dropping the full flow point allows the engine to run (steady state cruise speeds) in the mid to high 170's. Considering that the M96 engine has a significant number of "hot spots" (places with the cooling system where flow restrictions cause much higher than average coolant temps), and that these engines use a laminar flow oil to water oil cooler to keep the oil temp under control, reducing the coolant temps by this amount significantly lowers average oil operational temps, usually by 20F or more. That alone is huge in protecting the engine, regardless of what oil you run.

So (from practical testing and longer term running experience) here's what you get:

Significantly lower average coolant temps.

Significantly lower oil temps and longer oil life.

Here's what you don't get:

Problems.......You still have plenty of heat in cold (0F) ambient temps, no impact on the emissions system (no codes, no inspection rejects, etc.)

I really fail to understand why so many people balk at this concept..........

07-12-2009, 08:14 AM	#11
JFP in PA Registered User Join Date: Feb 2005 Location: It's a kind of magic..... Posts: 6,273	OK, let's put this one to bed: The LN thermostat will lower the point at which the coolant flow starts by about ~25 F. Considering that the dash gauge is inaccurate as Hell (when it reads between the "8" and "0" on the "180", the car is actually at about 205-210F), dropping the full flow point allows the engine to run (steady state cruise speeds) in the mid to high 170's. Considering that the M96 engine has a significant number of "hot spots" (places with the cooling system where flow restrictions cause much higher than average coolant temps), and that these engines use a laminar flow oil to water oil cooler to keep the oil temp under control, reducing the coolant temps by this amount significantly lowers average oil operational temps, usually by 20F or more. That alone is huge in protecting the engine, regardless of what oil you run. So (from practical testing and longer term running experience) here's what you get: Significantly lower average coolant temps. Significantly lower oil temps and longer oil life. Here's what you don't get: Problems.......You still have plenty of heat in cold (0F) ambient temps, no impact on the emissions system (no codes, no inspection rejects, etc.) I really fail to understand why so many people balk at this concept..........