Understanding Oil

[tofurun]

Well... This is about as basic as it gets. I have been reading exactly "what" oil means and what the numbers mean. I tend to agree with what a lot of the descriptions say about people really not fully understanding what the numbers are on oil. . Mostly because I had no idea myself (the book says use this so i use it). There I said it I DONT KNOW. well I did my research and am trying to fully understand all of it.

I know people are running different oil weights for things like oil coolers and turbos. BUT WHY. why do this. Turbos get oil hotter? Ok so use a thicker oil? well what about the engine specs from Toyota/Subaru? They say run 0w-20. now we have a oil cooler/turbo and we are running 0w-30. So we are increasing the Hot viscosity of the oil. Idk maybe I have been reading this explanations wrong. Heck I may be making it way more complicated than it really is. I am not asking what I should be running (yet). I am trying to understand the entire thing.

It may just be me but i think this would be a great write up for this section of the forum as a Sticky. Not trying to get flamed just trying to fully understand it.

[Mr.ac]

Your Google-fu is weak. Go learn young grasshopper.

[tofurun]

Originally Posted by Mr.ac

Your Google-fu is weak. Go learn young grasshopper.

Must. Try. Harder. To. Understand!!!!! AGHHHH

lol im still googling on like my 5th article at this point


EDIT: Wait wait wait. I just figured out the turbo deal becoming more lubricated cause the oil stays thicker. But that still doesnt account for it running in your engine. Good for turbo yes good for engine.... No?? So honestly if you are where im at when its Hot year round and freezes 2/365 days then the first number can be all the way to a 10w-20 because you never have cold starts like that. UGHHHH

Everything is telling me what. Its not telling me Why or circumstance like temperatures change and how that affects the specified oil to use.

[tofurun]

Originally Posted by Mr.ac

Your Google-fu is weak. Go learn young grasshopper.

can i ask you this. What oil are you running in your car?

[humfrz]

Originally Posted by tofurun

Well... This is about as basic as it gets. I have been reading exactly "what" oil means and what the numbers mean. I tend to agree with what a lot of the descriptions say about people really not fully understanding what the numbers are on oil. . Mostly because I had no idea myself (the book says use this so i use it). There I said it I DONT KNOW. well I did my research and am trying to fully understand all of it.

I know people are running different oil weights for things like oil coolers and turbos. BUT WHY. why do this. Turbos get oil hotter? Ok so use a thicker oil? well what about the engine specs from Toyota/Subaru? They say run 0w-20. now we have a oil cooler/turbo and we are running 0w-30. So we are increasing the Hot viscosity of the oil. Idk maybe I have been reading this explanations wrong. Heck I may be making it way more complicated than it really is. I am not asking what I should be running (yet). I am trying to understand the entire thing.

It may just be me but i think this would be a great write up for this section of the forum as a Sticky. Not trying to get flamed just trying to fully understand it.

Well, now, @tofurun ....... first off, your research is NOT complete, if you don't understand it. Most all the answers to your questions, can be found in the literature.

Yep, IMHO, you're making this oil thing waaay to complicated, for a basic understanding necessary, to drive your average FR-S in Georgia.

Oil, and more recently synthetic oil, has been used to lubricate internal combustion engines for years now ....... this is not a new science.

Back-in-the-day, () it was pretty simple ..... use 20 weight in the winter and 30 weight in the summer. Why? Because it was better to have the "lighter" oil in the crankcase in the winter so as the poor old 6V battery could turn over the old 200-400 cu. in. big iron engines. The 30 weight in the summer held up better under the higher heat.

To thoroughly understand oil and it relationship to the "physics" of the engine, one has to understand the "chemistry" of oil (including synthetics).

So, for you to have a through understanding of this concept ...... you have a lot of research ahead of you.

OR

...... you may take the humfrz approach and just read and follow the owners manual.......


humfrz

[Capt Spaulding]

If you have done the reading, the next step is to ask questions about the parts of the reading you don't understand. It would help to make the questions relatively tight and to the point. Or you could just do as Humfrz suggests and do what the owners manual tells you.

If you choose the former, beware. Re-read Dante's description of the words on the gate to Hell.

[Mr.ac]

Originally Posted by tofurun

can i ask you this. What oil are you running in your car?

On my BRZ 0-20 Mobile 1
My MR2 Trubo 10-30. Mobile 1
My MR2 Supercharge 10-30 conventional

Odd thing the supercharge did a lot better on regular oil than mobile 1. My butt dyno said so.

Pretty much what the manual recommends.
If on the silly idea I slap a turbo or supercharged to the BRZ I'll still use the same 0-20. With a lot of cooling.

[steve99]

Originally Posted by tofurun

Well... This is about as basic as it gets. I have been reading exactly "what" oil means and what the numbers mean. I tend to agree with what a lot of the descriptions say about people really not fully understanding what the numbers are on oil. . Mostly because I had no idea myself (the book says use this so i use it). There I said it I DONT KNOW. well I did my research and am trying to fully understand all of it.

I know people are running different oil weights for things like oil coolers and turbos. BUT WHY. why do this. Turbos get oil hotter? Ok so use a thicker oil? well what about the engine specs from Toyota/Subaru? They say run 0w-20. now we have a oil cooler/turbo and we are running 0w-30. So we are increasing the Hot viscosity of the oil. Idk maybe I have been reading this explanations wrong. Heck I may be making it way more complicated than it really is. I am not asking what I should be running (yet). I am trying to understand the entire thing.

It may just be me but i think this would be a great write up for this section of the forum as a Sticky. Not trying to get flamed just trying to fully understand it.

Have a look here for basic info on oil

http://www.pqiamerica.com/apiserviceclass.htm


have a read of this link , towards the end their some links on oil pressure vs temp .
http://www.ft86club.com/forums/showthread.php?t=81493



very rough giude

If your car is fairly stock and you just drive on the street in a cold to mild climate then just stick with the 0W20 synthetic as per manufactures recommendations for car.

If you drive the car hard or track car in warm to hot climates (ambient well over 30C and never gets below 0C) then probably a 5W30 or even 10W30 is better suited especially if you not running any form of oil cooler.

If you run an oil cooler and your keeping your oil temps below 115 C at all times then you can probably go back to 0W20, if your seeing greater than 120 C then either get a bigger/better oil cooler or run a slightly thicker oil like 5W30.

Its always better to keep the oil temps under control than to run really thick oils

modern synthetic oils dont break down till over 150C, its not generally the oil breaking down you need to worry about its the oil pressure dropping due oil thinning at high temps.

You rearly need to monitor your oil temps to determine the most suitable oil for your conditions and driving

[chaoskaze]

Originally Posted by tofurun

I know people are running different oil weights for things like oil coolers and turbos. BUT WHY. why do this. Turbos get oil hotter? Ok so use a thicker oil? well what about the engine specs from Toyota/Subaru? They say run 0w-20. now we have a oil cooler/turbo and we are running 0w-30. So we are increasing the Hot viscosity of the oil. Idk maybe I have been reading this explanations wrong. Heck I may be making it way more complicated than it really is. I am not asking what I should be running (yet). I am trying to understand the entire thing.

I don't know much but basically it depends on your application.
The reason to go to heavier weigh oil is just to keep the oil pressure the same under higher constant engine load/temp.

So if you track alot then it's normal to use higher weight oil even if it's N/A, there is a reason OEM TRD Japan oil is 0w-30. Some are even more extreme, like the RESPO 86 that's being sold in most AREA 86 http://www.respo.net/egn/respo86.html ("they said" It's a special blend of 5W-40 Design for our boxer engine on track.)


*then again I beat the crap out of my car with 0w-20s all 40k mile.....so ya..... your mileage may vary. >.>

[jarnojvv]

Motul 0w40 X-Max FTW

[wbradley]

Oil loses viscosity with increased temperature. Some oils maintain viscosity at higher temps but usually have a higher viscosity when cold.

There is a compromise using higher viscosity than OEM in that the can will not be as fuel efficient for daily driving but a forced induction or otherwise hyped up engine will reach higher peak temps, those temps will reduce oil viscosity which will in turn result in reduced oil pressure. This is risky for the engine's moving parts that rely on a certain pressure to keep things slick. For example on the HKS GT supercharger it is recommended to use 0W40 oil.

I would never recommend using that viscosity in a cold climate. It will not damage the engine to increase viscosity.

[Rameus]

Some of the science behind oil lubcication that is common in engines can be read here: https://en.wikipedia.org/wiki/Fluid_bearing

Note though, that not all engine components are necessarily lubricated hydrodynamically.

I'm sure you've seen some links to this already, but if you haven't, this site/forum has a wealth of oil info: http://www.bobistheoilguy.com/motor-oil-101/

[mav1178]

http://www.upmpg.com/tech_articles/motoroil_viscosity/

This is the first link that showed up when I Googled "oil weights explained"

You can get different/better results by playing around with keywords.

-alex

[tofurun]

Originally Posted by steve99

Have a look here for basic info on oil

http://www.pqiamerica.com/apiserviceclass.htm


have a read of this link , towards the end their some links on oil pressure vs temp .
http://www.ft86club.com/forums/showthread.php?t=81493



very rough giude

If your car is fairly stock and you just drive on the street in a cold to mild climate then just stick with the 0W20 synthetic as per manufactures recommendations for car.

If you drive the car hard or track car in warm to hot climates (ambient well over 30C and never gets below 0C) then probably a 5W30 or even 10W30 is better suited especially if you not running any form of oil cooler.

If you run an oil cooler and your keeping your oil temps below 115 C at all times then you can probably go back to 0W20, if your seeing greater than 120 C then either get a bigger/better oil cooler or run a slightly thicker oil like 5W30.

Its always better to keep the oil temps under control than to run really thick oils

modern synthetic oils dont break down till over 150C, its not generally the oil breaking down you need to worry about its the oil pressure dropping due oil thinning at high temps.

You rearly need to monitor your oil temps to determine the most suitable oil for your conditions and driving

Good reads. Thanks man. I knew i remembered seeing that video about the oil pressure in a thread somewhere.

Originally Posted by mav1178

http://www.upmpg.com/tech_articles/motoroil_viscosity/

This is the first link that showed up when I Googled "oil weights explained"

You can get different/better results by playing around with keywords.

-alex

This was the article that did it for me. Thank you!