Oil temp vs coolant temp

[Q45tech]

http://www.bobistheoilguy.com/...29178

Zoz, Steve, et. al., Engine Lubrication Model for Sump Oil Temperature Prediction SAE Paper 2001-01-1073

At 60 mph oil is ~ 20C hotter than coolant, at 4000 rpm it is 50C hotter"on the average, the Oil Sump temperature is always 1.2 to 1.43 times higher than the coolant temp. "

I wounder exactly how this applies to old Q.

It is important that the oil get to 212F to boil off all the condensation fast.

But that means you maybe driving with water in the oil for the first 5-10 miutes. Why you don't rev and engine until the oil is hot!!!!!!!!!!!!!

[lino]

How long do you usually warm up your car for in the morning before driving it?

[Q45tech]

Depends on soaked start temperature and oil low number viscosityIn ATL the longest is 7-8 minutes in winter AM [0-20F] since no room in garage for Q. I usually use 0-5wX in winter to help with cold flow.

Studies in Alaska show trying to use cold oil [below 100F] destroys engines fast. Why engine heaters.

BMW have a variable redline limit based on coolant temp.

[qship96]

Above freezing, I give it a good 15 seconds before drivivg gently{rpm's below 2000 til temp gauge is reading normal} Below freezing, it gets a 60-90 second warmup before driving gently......unless there is frost/snow on windows,then it idles til heater can melt the stuff and be scraped before moving.

[elwesso]

interesting... Id love to adapt a variable redline based on oil temperature...!

[qship96]

interesting... Id love to adapt a variable redline based on oil temperature...!

You already have one......its called your brain and your right foot!!!!! BMW must overdesign for complete morons.

[elwesso]

Well at the very least, it would be interesting to install an oil temp gauge on the bottom of the oil pan.. I wonder if you could use some sort of sensor that just would replace the drain plug, that would be a nice simple install..

[qship96]

Yeah, kinda like the oil pressure sender that just screws in, but reads temp-gotta be one out there to fit the drainplug opening!!!

[Infinitiguy19]

Yeah, kinda like the oil pressure sender that just screws in, but reads temp-gotta be one out there to fit the drainplug opening!!!

I think that will be a little tough to find.

I think its better to have a NICO ECU thats set to "Valet" for people worried about the po po AKA police during the end of the month (like me) or during the warmup period.
Modified by Paul Wall at 7:38 PM 8/26/2009

[Q45tech]

Remember the oil is the absolute COOLEST in the pan, don't confuse average with the crest factor which may be 50-150F hotter depending on where you measure.

Based on bearing clearences and observations the wrist pins and bottom of pistons is where the heat and varnish is concentrated.

The coolant temp [when colder than 176F functions as a decent signal as long as you use the dual connector sensor not the dash display.

What the summer overheat software is designed to warn you against by the loss of ignition advance [assumming you are sensitive to the feeling].