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View Full Version : Oil temp vs. water temp


krustindumm
09-06-2005, 11:59 AM
Anyone had both to compare?

I'm thinking of running oil temp instead of water temp. The temps should be the same, i'm just wondering which reacts faster, if there is any differece.

-Dustin

Var
09-06-2005, 12:17 PM
Z06 comes with stock digital read outs for both. The water heats up and cools down faster than oil. Oil temp and pressure is a good way to judge when it's ok to get on the throttle hard. I wait till it's up to 120ºF before i rev it 2500-3000rpm and 150ºF before i rev it to redline. By this time the coolant has been at full temp for a few minutes. I dunno if those are good numbers or not, just something i figured out in my own head. The oil temp can take a long long time before it reaches 210º and it usually never exceedes that for me.

PROJECTRB240SX
09-06-2005, 12:22 PM
Oil Temps Should Never Exceed Coolant Temps.... Most Oil Temp You Want To See Is 210 Degrees Than The Oil Breaks Down. Normally The Oil Temps Are About 10 Degrees Less Than Your Water Temp When Gauged At The Same Point On The Engine. Type Of Oil, Viscosity, Addatives All Contribute To Oil Temps.... So Not All Oil Will Be The Same Temp On The Same Engine.

90RS13
09-06-2005, 12:32 PM
Haven't been on in a while, cause I was moving from Germany back stateside, but anywho... when you said "the temps should be the same". That's not necessarily true. These two things have different specific heat values. (specific Heat being the amount of heat it takes to reaise 1g of something 1 deg celsius. Something with a low Specific Heat gets hot quicker.
Oil's specific heat Specific Heat is around 0.5. Water's specific Heat is around 1. So that would tell you that oil will get twice as hot as water with the same heat absorbed. But oil isn't as good a Thermal Conducter as water, so it won't absorb as much heat energy. Basically, at the end of the day, depending on of thermally conductive your oil is, what kind of blend it is (synth, weight, mineral), your oil temp gauge, may read the same as your water temp, it may not. The best thing to do for monitoring engine temp is water, because that's the cooling systems responsibility, and if the water temp changes drastically it could mean bad cooling problems.

Hope that helps, just my 2c.
-matt

Var
09-06-2005, 12:43 PM
Oil Temps Should Never Exceed Coolant Temps.... .


Oil temps on the track can approach 300ºF. Maybe 30º less with an oil cooler. Oil can run hotter than water.

TEALSQUEAL
09-06-2005, 09:39 PM
u want to wait until around 160 to start getting ont he car, i don't have a oil temp gauge in my car yet, but on my drag mustang i would always wait until it was around 160 before i stepped into it, then again i used 20w50 royal purple, i am using 15w50 mobil 1 in my sr though and i wait for the head temp to reach operating temp for atleast 5 min. before i ream on it

TEALSQUEAL
09-06-2005, 09:49 PM
u want to wait until around 160 to start getting ont he car, i don't have a oil temp gauge in my car yet, but on my drag mustang i would always wait until it was around 160 before i stepped into it, then again i used 20w50 royal purple, i am using 15w50 mobil 1 in my sr though and i wait for the head temp to reach operating temp for atleast 5 min. before i ream on it

originalsin
09-06-2005, 09:54 PM
yea id think youd wana watch the oil temp i mean, if that gets to hot you coke your oil, which can rly fuck shit up, and if your oil is to hot, then you know your coolant must be too

PROJECTRB240SX
09-07-2005, 07:03 AM
If You Let Your Oil Temps Reach 300 Degrees Your An Idiot..... In Every Race Vehicle I've Ever Driven (besides Air Cooled Go-karts) The Oil Temperature Never Exceeded 220 Degrees. This Is Even After Endurance Races Of 50+ Laps Also In Formula Fords And Mazdas. The Effectiveness Of Oil Is Seriously Degraded After 210 Degrees. Oil Has A Sweet Spot Of 175-230 Degrees, Before Or After That The Oil Isn't Doing Its Job Properly.

You Never Want Your Oil Temps To Exceed Your Water Temps.... If It Does Consistantly And Holds There You Have A Design Flaw In The System. Hell The Stock Sr With Its Tiny Pan And No Cooler Oil Teps Only Get To About 195 After Spirited Driving In The stock System, When You Start Changing Things You Have To Make Changes To The Entire System To Properly Maintain Integrity.

Var
09-07-2005, 11:00 AM
Umm..i dunno where you're getting this information that i'm an idiot, but you're probably right. Oil will run to past coolant levels pretty quick. . The general concensus on the Ls1 boards are shut it down on the track when it reaches 270-280. Reaching 300º is not acceptable but it'll simply happen if you keep open lapping with certain cars. And normal oil operating temp is 210 degrees at CRUISE, so if you logically think about it, 250+ temps would be normal when hot lapping.

PROJECTRB240SX
09-07-2005, 12:17 PM
Ohh Your Talking About Ls1's.... Those Are Weird Motors, They Are Actually Designed To Run On 230 Coolant Temps And Up To 260 Oil Temps. This Was Designed To Keep Emissions Down And Lubricity Up, But If You Look At The Manual On The Late Ls1/2 They Prefer Oil Changes At 1500 Miles And Recommend Synthetic 20w-50 In High Performance Applications (which Is Designed To Handle Those Constraints).

Your Only An Idiot If You Let Your Sr/ka/ca Oil Temp Get To 300 Degrees (which Is What I Thought You Were Talking About). Like I Said Before In My Formula Ford And Mazda Race Cars We Never Got Oil Temps Above 220 Degrees... The Systems Were Designed To Keep Oil In Its Sweet Spot. Even Driving My Sr Hard I Never Got Oil Temps Above 195 While Coolant Got To About 205, Which Is Safe And Happy Levels. I Actually Plan On Getting My Oil To About 215 Degrees And Lowering Cooling Temps... But This Is Simply To Help Lubrication Of The Turbo And Engine Bearings I Also Plan To Run Synthetic 20w-50 Or Straight 30 Sae For Best Longevity And Lubricity.

Var
09-07-2005, 01:32 PM
Ohh Your Talking About Ls1's.... Those Are Weird Motors, They Are Actually Designed To Run On 230 Coolant Temps And Up To 260 Oil Temps. This Was Designed To Keep Emissions Down And Lubricity Up, But If You Look At The Manual On The Late Ls1/2 They Prefer Oil Changes At 1500 Miles And Recommend Synthetic 20w-50 In High Performance Applications (which Is Designed To Handle Those Constraints).



Well LS1 or not..if you say the oil is past it's efficiency level then what's the point of running it so hot?..but you're right. they do run hot coolant and oil temps. Also the recommended oil change is at 15,000 not 1500 (i change mine @ 3000). The things is the car was built to run hot temps even with the 5W-30 and the Z06 was somewhat built for track usage and GM knew that the car's oil temps would be that high on the track anyways. All new cars are built like this. Especially Bimmers. My friend's mom has the new 645 and the oil gets WAAAY hotter than my Vette. Also i've heard that on Sr's the oil temps get too hot, but i never had a oil temp guage on mine so i wouldnt know. All i know is they overheat less with a bigger oil pan.