The Goods On Oils

[djr81]

Pressure is directly proportion to viscosity, the thicker it is the higher is the pressure. This also mean higher pressure will have lower flow rate. You need both flow rate and pressure to fully optimize the operation of the oil system. IMO 50wt oil is just too thick for most application except racing or autocross....

Rather than start an argument I would rather pose a question.

First things first what you have said is partly correct. A higher viscosity fluid will create a larger pressure difference when measured from one end of the pipe it is being pumped in to the other. This means a higher output pressure at the pump is required to achieve the same flow rate.

BUT

There is more than one type of pump. For a centrifugal pump (like your water pump) the output pressure has a huge effect on the flow rate of the pump. For a positive displacement pump it has ABSOLUTELY no effect.

So what type of pump is your oil pump?

[Cubes]

Rather than start an argument I would rather pose a question.

First things first what you have said is partly correct. A higher viscosity fluid will create a larger pressure difference when measured from one end of the pipe it is being pumped in to the other. This means a higher output pressure at the pump is required to achieve the same flow rate.

BUT

There is more than one type of pump. For a centrifugal pump (like your water pump) the output pressure has a huge effect on the flow rate of the pump. For a positive displacement pump it has ABSOLUTELY no effect.

So what type of pump is your oil pump?

It does when the bypass is wide open; in essence the thicker oil creating high pressure also causes a huge effect on the flow rate of the pump as it has to dump a lot more oil to hold its specified oil pressure.

With a 5w40 I see ~90-95psi of oil pressure over 3500rpm.

[LatinR33]

anyone?? 0w40 ok for an 11 year old skyline with 90,000km's

Edited May 31, 2007 by LatinR33

[SS8_Gohan]

i would say it's fine

wouldn't trust an import odometre though...

[LatinR33]

Nah i'll never take the odometer reading as gospel hehe. I just want to know if its a safe things to use. Ive been going through this thread and man ive got a headache and I just want to know what oil to buy tonight when i go down to supercheap. I just want something good quality and something quietens down my lifters abit during start up thats it. any suggestions for my 1996 R33?? Im sure its not rocket science but after reading a few pages im like damnnn oil choice is a massive decision.

[SS8_Gohan]

yeah, you've asked quite a few times

I've answered with Mobil 1 a few times as well

0w40 in my car, took a little less than 5 litres i think. As i've said before, RB lifters are fairly noisy anyway, but the Mobil 1 did quiet them down a little, for me. NEO R34, don't know if that makes a difference.

i can't say anymore than what i've already said. I've got 0w40 in my car, and yes it made the lifter less noisy.

can't answer your question any more straight forward than that. And if people like Trex101 are telling you it's fine, that it's 100% cool. They're the sorts of people in this thread that i made my oil choices from. Trex101 and khunjeng, etc...

[LatinR33]

ok ok ok thats cool sorry didnt mean to be a pain understood

[SS8_Gohan]

that's cool

mate, i was exactly the same, worrying about which oil to put, concerned about this and that. But some of guys in this thread REALLY know their oils. Mobil 1 is a good starting point, at a reasonable price and having 0w40 is fine. Then you can go German Castrol, Redline, Motul after that if you're keen.

i know exactly what it's like to be paranoid bout the car, especially with the oils. I also did my gearbox and diff at the same time, so i was 3 times as paranoid! haha

Maybe just PM Trex101 or khunjeng with your EXACT concerns and worries, and grab their opinion

[adzR34]

This Harold guy from performancelub.com.. is he in syd?

[khunjeng]

This Harold guy from performancelub.com.. is he in syd?

Melbourne.

[adzR34]

Melbourne.

Ah crappp, do u think it would be worthwhile getting mob1 off him and shipping to syd. it'll probli be the same cost as local stores hay?

[SS8_Gohan]

nope, will still be cheaper i'm pretty sure Even melb people have to pay for postage. The difference isn't that great between posting here or interstate.

[adzR34]

nope, will still be cheaper i'm pretty sure Even melb people have to pay for postage. The difference isn't that great between posting here or interstate.

ah okay yeh ive found those rates they aint that bad...

Pretty keen on the royal purple stuff for that price, anyone using this in theyre cars?

[Hotwire]

Guys,

Was just enquiring about gearbox oils at the Outlaw Speed Shop here in Adelaide, and got to talking about engine oils too. I was passed on this article to read/keep and had to share with everyone as it has some REAL eye openers.

I will more than likely be using the Royal Purple next, far and above the others for value for money I reckon. Almost makes me want to dump the Motul 8100 excess in there now!. However got to say that the Valvoline shocked me!

Cheers

Lee

Oil_Compar.pdf

[Cubes]

Royal Purple value for money? I always assumed they would be exxy.

What did they want for 5ltrs?

[Hotwire]

Well I didnt get a price from Outlaw, but the listed price in the comparo is $79.99 compared to $92.99 for the Motul 8100 Excess, which you can get for cheaper than that.

By value for money, i meant for similar dollars to Motul, get far better protection for a full synthetic.

For a Semi synthetic, seems the Valvoline durablend is the go.

Its all in the PDF I attached to my post

Edited June 8, 2007 by Hotwire

[Modena]

Ive just got another 5 liter bottle of Castrol Edge 5w-30 oil for my car. Was thinking of 0w-40 but then decided against it as the first was cheaper.

[Trex101]

Guys,

Was just enquiring about gearbox oils at the Outlaw Speed Shop here in Adelaide, and got to talking about engine oils too. I was passed on this article to read/keep and had to share with everyone as it has some REAL eye openers.

I will more than likely be using the Royal Purple next, far and above the others for value for money I reckon. Almost makes me want to dump the Motul 8100 excess in there now!. However got to say that the Valvoline shocked me!

Cheers

Lee

This article from StreetCommodore is very misleading, this Timken test are only good for grease, not oil. The editor has admitted the test is flawed and not representatives of actual engine condition.

StreetCommodore reply:

http://www.streetforce.com.au/news/01_oils_aint_oils.php

[Hotwire]

Wow,

Thanks for pointing that out. So the verdict is still out then LOL

[Trex101]

Wow,

Thanks for pointing that out. So the verdict is still out then LOL

You know, i can get better wear reading with head and shoulder shampoo then all these oil tested. The chorine in there are a very good extreme pressure additives, it just that when you include it in your engine oil combine with moisture, you will form hydrochloride acid.