Another oil thread

#25

donstevens wrote:

[quote]Further comment on the sparkly stuff and low oil pressure.

Does anyone really know if engines fail because of low oil pressure or if the oil pressure drops because if all the sparkly stuff clogging the oil pump intake? My guess is that by the time a driver notices the oil pressure drop the damage has already been done

Don[/quote]

Sparkly stuff won’t clog the oil pump intake, it would take a piece of foreign matter the size of a quarter or so.

Engines shouldn’t fail because of low oil pressure. All thepump really has to do is keep oil flowing to the bearings as fast as it’s getting squirted out of the bearings. So as long as the pump is a little more capable then the most oil that can get squirted out, then the pump will have a little remaining flow capacity. But when it comes to the oil pump, it’s more about providing adequate flow then pressure.

As we all know, worn bearings have larger gaps which flow more oil. It’s the inability of the pump to sustain high pressure in the face of less flow resistance that results in the loss of pressure. A gradual loss of pressure is a symptom, not a cause of anything.

Castrol GTX is crap. The 20W50 Syntec, however, is only “sometimes crap”. Castrol doesn’t publish specs on teir oil. That makes tribiologists mistrust it, and it also allows them to change their additive package as often as they want and know one will know. I’ve see oil analyses that said 20W50 Syntec that indicated that it was ok, and some not ok.

The biggest problem with GTX tho is not an issue of bearings, but an issue of the anti-wear additives needed by the cam, rockers, rings and cylinder walls.

#26

I found the Castrol Edge 10w-60 on their website. the only specs listed were the VI, 100c and 40c numbers. The fact that BMW recommends using it in all new m cars and 15k changes makes me want to try it, but not in a junkyard motor.

#27

turbo329is wrote:

Adding on to Ranger’s comments about Castrol and your comments about Edge 10W60. The 10W60 that BMW recommends for M cars and even the 5W30 that BMW dealers carry IS NOT the same stuff that you can buy over the counter here in the states. The BMW labeled oil is blended in Europe to a completely different set of specs as in America.

American Castrol was the first oil company to challenge the notion that group III hydrocracked (highly refined petroleum) oils can be called synthetic. Mobil sued them stating that their Group IV oils (formulated from a derivative of natural gas I belive) are the only true synthetic oils becaused they are manufactured in a much more expensive procedure than hydrocracking. Castrol won the suit and paved the way for every oil company (including companies like Mobil, Amsoil, and Royal Purple) to offer a lest costly group III oil labled “synthetic” and still charge full synthetic prices. Virtually every brad name “synthetic” that one can buy of the shelf in Walmart and auto parts stores today is the cheaper group III oil.

Having said that, the Group III products still perform extremely well in 98% of the applications. It is the bait and switch that Castrol America started that pisses me off.

Don

#28

Hmmm, interesting thread guys.

So is the Advance/AutoZone Mobil 1 I buy a Group III or Group IV oil??

#29

Ranger wrote:

[quote]Castrol GTX is crap. The 20W50 Syntec, however, is only “sometimes crap”. Castrol doesn’t publish specs on teir oil. That makes tribiologists mistrust it, and it also allows them to change their additive package as often as they want and know one will know. I’ve see oil analyses that said 20W50 Syntec that indicated that it was ok, and some not ok.

The biggest problem with GTX tho is not an issue of bearings, but an issue of the anti-wear additives needed by the cam, rockers, rings and cylinder walls.[/quote]

Damn it. Castrol GTX 20w50 is what I have been running. If you are going to slam my oil, can you recommend a cheap 20w50 to use instead? I believe I have seen you mention Valvoline VR1? I don’t really want to run one of the expensive synthetics, and I am too lazy to do any research on it.

#30

I’ve decided to go against my brothers recommendation and switch from regular 20w-50 VR1 to synthetic 20w-50 VR1 in the turbo motor. The motor probably probably has less than 1k miles on it and is full of fancy ceramic and Teflon coatings on the inside, so it seams like a good candidate.
I’m going to change the oil and filter again on the i motor again and examine it. The op light has stopped coming on at idle and it doesn’t seam to be getting progressively worse as I expected.

#31

I’m switching from Valvoline VR-1 to Brad Penn. It’s cheaper and has far better specs. I just got box of Brad Penn 15W40 and I’ll get a box of 20W50. Then I’ll do some testing and decide on a visc.

For the lazy…just use Mobil1 15W50. Not 15W50 “enhanced performance”, “enhanced mileage” or “enhanced breasts”, just 15W50. It’s not the cheapest and it’s not the best. But it is pretty cheap and pretty good.

#32

i think you mean 15w50, don’t think mobil1 comes in 20w50

#33

jtower wrote:

You’re right, good catch. I’ll change it.

#34

I had the op light flash at idle…ran some Kendall GT 1 straight 50 in it and a bottle of STP, ran fine on the street for a long time, then ran it in a 3 hour enduro, car finished, ran fine but was getting noisey. While running the straight 50 and STP the light never flashed again, if I had not raced it the motor probably would have lasted forever on the street…

Al

#35

Fred42 wrote:

[quote]Hmmm, interesting thread guys.

So is the Advance/AutoZone Mobil 1 I buy a Group III or Group IV oil??[/quote]

Fred - One could spend a day on BITOG looking and probably figure it out. I heard rumors (interet rumors that is) that the standard drain products are group III (possibly a III/IV blend) and that extended drain Mobil-1, and the V-twin is still the real deal Group IV.

Don

#36

The main reason I use VR1 is because it is on the shelf at my local store. If I had to order something I would probably put more thought into it. The VR1 syn better be twice as good as VR1 because it’s twice the price. I also decided to change oil filter brands since autozone actually had the correct bosch and mobil one on the shelf instead of just fram. Bosch for the i and mobil one in the iS.

#37

Amsoil Dominator Synthetic 15W-50 Racing Oil (RD50)

#38

tpr jules wrote:

I just looked that up. It looks like really good stuff. High HTHS, high ZDDP, good anti-wear test results (see graph), and low 100deg visc. Nice.

http://www.amsoil.com/storefront/rd50.aspx

#39

donstevens wrote:

[quote]Fred42 wrote:

[quote]Hmmm, interesting thread guys.

So is the Advance/AutoZone Mobil 1 I buy a Group III or Group IV oil??[/quote]

Fred - One could spend a day on BITOG looking and probably figure it out. I heard rumors (interet rumors that is) that the standard drain products are group III (possibly a III/IV blend) and that extended drain Mobil-1, and the V-twin is still the real deal Group IV.

Don[/quote]

Thanks Don! While I passed Chemistry, most of this oil discussion is “above my pay grade”. :lol:

#40

Where is oil temp normally measured at? I always read that oil temp should be in the 200’s but my iS always shows the oil temp lower than coolant temp. While my cylinder head temp is 190 my oil temp is only 140. My brother has been the caretaker of my iS for the past few years and I’m not sure where he has all the sensors at.

#41

Ranger wrote:

[quote]I’m switching from Valvoline VR-1 to Brad Penn. It’s cheaper and has far better specs. I just got box of Brad Penn 15W40 and I’ll get a box of 20W50. Then I’ll do some testing and decide on a visc.

For the lazy…just use Mobil1 15W50. Not 15W50 “enhanced performance”, “enhanced mileage” or “enhanced breasts”, just 15W50. It’s not the cheapest and it’s not the best. But it is pretty cheap and pretty good.[/quote]

Isn’t taking oil advice from you like taking dieting advice from a fat chick?

I mean, how many engines have you exploaded? :stuck_out_tongue:

#42

I like to sample oil temp in the pan…a good indication of the temp of your bearings. CB

#43

turbo329is wrote:

There’s no perfect answer. Much of data collection isn’t so much absolutes but comparing against a baseline. No matter how you collect temp or pressure data, once you’ve been doing it a while you’ll be able to spot something out of the ordinary quickly. And this is true no matter if you are measuring temp before or after a cooler or radiator, or pressure in various places.

Oil pressure is tricky because it is so dependent on temp and oil choices. Consider…Thick oils show greater OP because they present more flow restriction. But thin oils exchange heat better so if you have an oil cooler they dump more heat and come back to the engine cooler. Since they come back cooler they come back thicker. So the lower visc oil could result in higher OP, if the OP is measured before the oil gets heated up again.

So it depends on oil choices and where you are measuring things. My point is that it’s hard to make absolute comparisons. My engine may run hotter or have higher OP then yours, but there could be a half dozen variables causing that, none of which are cause for concern. But if your hot OP drops 10psi over the course of a couple events and you’ve not changed anything, you know something is going on.

#44

mcmmotorsports wrote:

[quote]Ranger wrote:

[quote]I’m switching from Valvoline VR-1 to Brad Penn. It’s cheaper and has far better specs. I just got box of Brad Penn 15W40 and I’ll get a box of 20W50. Then I’ll do some testing and decide on a visc.

For the lazy…just use Mobil1 15W50. Not 15W50 “enhanced performance”, “enhanced mileage” or “enhanced breasts”, just 15W50. It’s not the cheapest and it’s not the best. But it is pretty cheap and pretty good.[/quote]

Isn’t taking oil advice from you like taking dieting advice from a fat chick?

I mean, how many engines have you exploaded? :P[/quote]

Mike, You don’t want me to build an engine for you. Heck, beyond something easy like swapping heads, I’m done with engine work. But there’s a lot of oil information out there if you’re willing to spend a couple months reading. My reading comprehension skills are at least average. From a 3rd party’s perspective it’s a lot more efficient to simply read the cliffnotes that some obsessed geek provides, then go read it all yourself and reach the same conclusions.

But if I go to the bother of trying to provide you with those cliffnotes, I’d encourage you to disagree with physics, chemistry and data, or keep a civil tongue.