Ideal Oil Temperature

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228
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NE Oklahoma
Is there an ideal temperature range for oil that will give the motor the best lubrication ? I know the basics: oil should not be too cool, nor too hot. But is there a consensus as too the "perfect" temperature ? The oils being used are Mobil 1 15w-50. And Mobil 1 0w-40 The engines are vintage Ford iron High Performance 289's and various Ford FE series iron engines, ( 352, 390, 427, and 428 ci. ). All will see some high speed endurance racing, as well as street use. any information will be appreciated. Z.
 
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Cool engines. Any of them "side-oilers"? Mechanical flat-tappet only FEs. I watched the oil temperature an industrial MTU 5,000 hp 4-stroke locomotive engines. When they are idling or just being moved around, the oil temperature is generally around 200F. Start working them and the oil temperature goes down to 170-180F When they are on a long 30+ minute pull at 4,400HP (to the track, not engine gross), the temperature will slowly rise to 210F then suddenly drop to 190F and stay there. the oil is a zink-free SAE 40 or 20W40 Automotive engines?
 
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zray

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Originally Posted By: used_0il
Cool engines. Any of them "side-oilers"? Mechanical flat-tappet only FEs.
The HiPo 289 and the 427 / 428 engines are flat tappet solid lifter engines. The 352 and 390's are flat tappet hydraulic lifter engines. The 427 is a side oiler..
Originally Posted By: Chris142
Hot enough to boil moisture out. 212 ish ?
I was thinking over 200 F. But I don't know if there is a consensus for the low temp, or the "safe" high for that matter . Z
 
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I don't see a problem with going "off topic" with this one. I know someone with a 66 just like yours with a 427 side. And some crazies with the 428 crank in them. 453 FE ?
 
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Manchester, England
Some additives need to get up to a high temperature to activate; Some oils (Redline) are very resistant to Breaking down at higher temps.. Upto 120 degrees Celsius is A-OK. If you regularly see 130ish then a thermostatic cooler aiming for between 110 and 120 would be perfect.
 
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Sunny Florida
I had conversation with Mobil One folks back in 05 about race day oil temps in my car which can easily touch 300 degrees F. I was told that was well within the designed parameters for both the engine and the oil. I am sure Redline has even greater temperature resistance in its formula (or at least it should for the price!).
 
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5,651
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Iowa
150-160 (oil temp) before beginning your flogging session, up to 260-270 or so oil temp. Not that the oil couldn't physically handle more, but at or above that temp, you may not have enough viscosity to protect the engine. Not sure what the exact viscosity requirements are for your engines. Do you have an oil cooler installed?
 

zray

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Originally Posted By: The_Eric
Not sure what the exact viscosity requirements are for your engines.
10w-30 was specified for "normal" use. . I don't recall what we using in our racing Fords back then ( I was only 14), Of that was in 1965, No great synthetic lubricants in those years. For the flogging these engines nowadays, especially the duty the HiPo 289's are seeing, I've been using Mobil 1 15w-50 (since 1999) with excellent results.
Originally Posted By: The_Eric
Do you have an oil cooler installed?
I'm putting them in, Initially in the 289's. Hence my questions. Wondering what thermostat to utilize. The oil coolers were used by Carroll Shelby in his racing GT350's with the 289 HiPo engines in '65/'66 when he beating the Corvette Sting Rays regularly, and taking the SCCA championship in the process. He wouldn't have put them in I'd there hadn't been some issues with the ((dino) oil getting too hot. Z
 
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The viscosity requirements of your engine will vary with bearing clearance, load, temp, RPM and so on. A 30 grade would have served just fine when the engine left the factory and was driven normally- or with the occasional flogging. Sustained track use is a different story though. If your bearing clearances are stock or close to stock, I'd say your choice of oil is likely fine, and keeping the temps at or below 230 should give you plenty of reserve viscosity. To see the effects of temp on visc., use can use a calculator to plot it's thickness against temps... I'd say as long as you have around 10cst or more at temp, you'll be okay. Member "widman" has a good one- He has a website (search Richard Widman) and you should find his calculator. You'll need some basic specs from the oil (can be found on the PDS) like viscosity at 40c and viscosity at 100c.
 
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According to one of the big Japanese OEMs, idea oil temperature is 80C/176F. I don't remember how much it was, but in another paper oxidation was described to go up some % for every 10C beyond 80. As of 2003, this OEM was able to estimate oil temperature -6.6 to +3.6% without having an oil temperature measurement, for their oil life monitoring system. You can see why oil analysis by Blackstone is so lacking. TAN and Oxidation, and to a lesser extent nitration and sulfation are also extremely important.
 
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1,445
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Dana Point, CA
Originally Posted By: vinu_neuro
According to one of the big Japanese OEMs, ideal oil temperature is 80C/176F...
Interesting to view the compromises faced between too low and too high. Not many GT-R track days or even long interstate uphill pulls aboard the family sedan factored into those 'ideal' temperatures as 176°F is frequently exceeded in almost all modern machines during the summertime months. Improved thermodynamics and environmental efficiencies perhaps?
 
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Originally Posted By: splinter
Interesting to view the compromises faced between too low and too high. Not many GT-R track days or even long interstate uphill pulls aboard the family sedan factored into those 'ideal' temperatures as 176°F is frequently exceeded in almost all modern machines during the summertime months. Improved thermodynamics and environmental efficiencies perhaps?
Just because 176F is ideal from the lubricant degradation pov, doesn't mean it's or ideal (in terms of what's necessary to make it possible) or feasible from a system pov. But it highlights the importance to keep oil temperatures as low as possible, especially in track cars. And have a thermostat on the oil cooler for dual use cars.
 
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3,381
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I haven't seen the mention of nitration and TAN come up when used automotive oils are tested. Perhaps these type of engines do not hold the oil temperature high enough and long enough for nitration to become an issue, in the short service life of non-commercial applications. If you read through a product listing from any of the oil companies you will find "gas engine oils". Those are lubricants for engines that that run on natural gas or LPG. In that section you will find reference to TAN and nitration. The engine oils are specific for manufacture approval and fuel type.
 
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43,676
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'Stralia
Originally Posted By: vinu_neuro
According to one of the big Japanese OEMs, idea oil temperature is 80C/176F. I don't remember how much it was, but in another paper oxidation was described to go up some % for every 10C beyond 80. As of 2003, this OEM was able to estimate oil temperature -6.6 to +3.6% without having an oil temperature measurement, for their oil life monitoring system.
For the R and O (Rust and Oxidation inhibited) Steam Turbine Oils, the rule is life is halved for every 10 degrees over 80C...i.e. at 100C, it's got 1/4 life. Not sure how this correlates to IC engines, as the oil exiting (say) the big end will be at least 20C over the bulk oil temps. My l67 Caprice after 25km on highway (1,800RPM cruise) will have immediately post stop, and with a type K thermocouple dropped down the dispstick tube to around the mid point of full and add will have 105-115C...it's a mix of what's come off the big end and rods, and what's drained down from the top end...some of the lubricant has been exposed to easily 130C...in an environment of blowby gasses.... So I'm not sure the rule of thumb applies equally to engine oils...although the turbine oil lasts 100,000 operating hours, engine oil 300-400. Maybe it does. As to estimating oil temperature, for oil life, the 10% range that you quoted should be easily estimable with engine speed and air inlet temperature as the inputs if you know enough about the engine, and the OEM has that. e.g. again my Caprice, 105-110C at 1,800 RPM...if I hold it in "2" for 10km (3,800-4,000 RPM), the thermocouple will read 125C easily (in 2-3C ambient)
 
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The real question is what temps are you seeing? and psi at those temps? Besides the 15w50 and 0w40, the M1 HM oils have a good additive package and available in 5w30, 10w30, and 10w40. And the truck 5w40 is another great choice. 300f in racing is great if you tear down and inspect after each race. Not feasible in a daily driver. Water evaporated at room temp so 212f isn't need if it is properly vented(pcv..). 140-220f is a good goal average. Above or below and you need to address it with thermostat, sump size, cooling or heating mods...
 

zray

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228
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NE Oklahoma
Originally Posted By: Greasymechtech
The real question is what temps are you seeing? and psi at those temps?
I don't have the oil temp gauge, or the oil cooler installed yet. So oil temperatures are unknown. Am trying to get an idea of what thermostat to use with the oil cooler. Hot oil pressure is 72 psi at 3,000+ rpm. Bypass set at 90 psi.
Originally Posted By: Greasymechtech
140-220f is a good goal average. Above or below and you need to address it with thermostat, sump size, cooling or heating mods...
sounds like 200 F is a good goal to shoot for. Z.
 
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10,921
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Cincinnati, OH, USA
Originally Posted By: vinu_neuro
According to one of the big Japanese OEMs, idea oil temperature is 80C/176F. I don't remember how much it was, but in another paper oxidation was described to go up some % for every 10C beyond 80. As of 2003, this OEM was able to estimate oil temperature -6.6 to +3.6% without having an oil temperature measurement, for their oil life monitoring system. You can see why oil analysis by Blackstone is so lacking. TAN and Oxidation, and to a lesser extent nitration and sulfation are also extremely important.
Vinu-was that OEM paper recent (with synthetic oil), or older (with conventional)? Would believe even a syn blend could handle higher than 80C easily?
 
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Columbus,Nebraska
Is 176F hot enough to boil off the condensation in crankcase oil that builds up due to city driving? I think most vehicles have 180/190 thermostats. Is that hot enough to produce oil temperatures sufficient to boil of contaminants?.
 
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