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For those of you running an AccessPort, what temperature is too high for oil? I've seen 197 degrees in my oil temperature once in a while. Is this too high?
 

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"" stolen from Google:
""A quality conventional motor oil will tolerate oil sump temperatures of up to 250 degrees, but starts breaking down over 275 degrees. The traditional approach is to try to hold oil temperatures between 230 and 260 degrees""

And another separate quote:
""Cold engine oil causes excessive frictional drag on the bearings and cylinder walls. A quality conventional motor oil will tolerate oil sump temperatures of up to 250 degrees, but starts breaking down over 275 degrees""
 

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I have seen oil temps as high as 235 on the track here in the Florida heat. I added an oil cooler to keep temps down but changed to a 200 dgeree thermostat for street driving. I felt the 180 degree thermostat wouldnt allow oil to reach a high enough temp to boil off moisture.
 

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Highest I've ever seen on mine was 205, usually it will stay at 189-195 when its fully warmed up (I have a hour drive on the highway to work everyday).
 

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200* is perfectly normal. The engine has a liquid to liquid oil cooler, that cools the oil with engine coolant. While driving normally, this keeps the oil close to coolant temp. Also, the temp reported by the gauge is "calculated". There is no oil temperature sender on this engine. The PCM calculates the theoretical temp based on several parameters. It is NOT an exact reading. If you make any changes to the cooling system on the car (lower temp thermostat, additional oil cooler, oil capacity, radiator, etc.), the reported temps are no longer accurate.

If you're using a good synthetic oil, it can intermittently tolerate 300* temps. I know of a few vehicle platforms that run the oil over 230* regularly, without any issue.
 

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I have seen oil temps as high as 235 on the track here in the Florida heat. I added an oil cooler to keep temps down but changed to a 200 dgeree thermostat for street driving. I felt the 180 degree thermostat wouldnt allow oil to reach a high enough temp to boil off moisture.
I've wondered about this myself, if I remember right, the oil has to get up to at least 212 to boil away the condensation. I remember doing some research on this because the oil in our Harley's would get so freakin hot and I read that along the way somewhere.
 

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I've wondered about this myself, if I remember right, the oil has to get up to at least 212 to boil away the condensation. I remember doing some research on this because the oil in our Harley's would get so freakin hot and I read that along the way somewhere.
Exactly, I find with the 200 degree thermostat, I can keep it at 210-215 degrees, even when pushing the car.
 

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I've wondered about this myself, if I remember right, the oil has to get up to at least 212 to boil away the condensation. I remember doing some research on this because the oil in our Harley's would get so freakin hot and I read that along the way somewhere.
It doesn't have to get to boiling temp to evaporate condensation...Liquid water will evaporate at 32*...but higher temps obviously speed it up. IMO, oil should reach at least 180*.

Harleys have high oil temps because the engine is air cooled, and they have no oil cooler, or at best, one that is minimally sized. If you're riding in high ambient temps, I'd be running a quality synthetic oil...funny though that Harley used to specifically say NOT to use synthetic, back in the EVO days. Never made any sense to me, and I used it anyway.
 

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Yep, normal Temps vaporize volatile oil stuff (residual gas, water, broken down oil)

But temps also effect viscosity too.

The viscosity difference from 170* to 270* could lead to a weaker oil film that protects the bearing and ring surfaces.

Guy from Redline covers it in this video: (also a good starter to learn about racing oil)

 

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Yes, but....everyone uses an industry standard to measure cST at 212°/100°. Thus, your 10W30 (or any oil weight on the market for that matter) is a 10W30 at, and only at 212°. So for an oil standard, 212° on the oil temp is the ideal temp to be at because that's what the engine was designed to run. I know people freak out when they see 200°+, and/or think that oil should be kept as cool as possible, but such is not the case.
 

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You really don't have to be worried about the oil not getting up to temperature since the St has piston oil squirters. The oil coming off the pistons is going to be a solid 30 to 50 degrees warmer than the ambient oil temperature. So the the moisture in the oil getting burned out on the oil getting sprayed on the pistons. 190 degree ambient oil temperature means you have 220 to 240 degree oil coming off the pistons. That means also, if you have 250 degree ambient oil temperature and its getting another 50 degrees off the piston running the car hard on the track your oil is smoking at 300 degrees. If you read up on oil cooled pistons in airplane engines there has been tons of research on oil temperatures coming off pistons. If you want proof after a track day where you oil is up to 250 degrees drain it and send it in for analysis it'll come back with some very bad viscosity ratings.
 
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