Official S65 Bearing Specification/Clearance Wiki

[regular guy]

As long as the stroker cranks and connecting rods are made to the same exact specifications as the factory parts, then they remain good analogs to compare for bearing clearance issues. In this particular case of the engine discussed in the opening article, all of the vital measurements were effectively identical to factory: journal sizes, journal width, thrust bearing journal width, connecting rod width, connecting rod big end diameter were all effectively the same as factory. Most measured identical; with a select few 0.00005" different in one direction or the other. If one guy wants to claim that +/- 0.00005" variance is meaningful on the aftermarket parts, then let him try. It would be a foolish endeavor because the factory rod journals we measured also showed +/- 0.00005" variance as well, and the factory main journal variance was much worse than that.

But where aftermarket parts are known to exist, I believe they should be documented to give the reader the fair opportunity to judge for him/herself the relevance.

[chris719]

stock Z4M
http://www.zpost.com/forums/showthread.php?t=863393

supercharged Z4M
http://www.zpost.com/forums/showthread.php?t=787684


All showing the same wear pattern as observed in S65 and S85. If you consider the number of years BMW has had to address this "issue", I'd call it planned obsolescence.

already seen by many, but another link discussing the issue:
http://www.m3post.com/forums/showthread.php?t=887379

[regular guy]

Originally Posted by swamp2

No one on that side can even give a ROUGH COUNT of how many motors that are entirely or largely stock and have exhibited this excessive wear. I've only asked for this about 3 times...

I know I've said that I wouldn't want to guess because I don't like to guess. But it seems that you want a guess. Ok, I'll guess.

I will guess 200-500 completely bone stock, factory motors, without any mods, who have religiously serviced their cars at BMW dealerships in the USA alone. I only have six or seven contacts who share information over the past four years. But when they share, they often tell of multiple cars per month, and sometimes multiple cars at a time. So if you extrapolate those estimates to the rest of the USA, then I'll say 200-500 is my guess.

There, you happy for a guess that nobody can prove or stand behind as anything but a guess? Well, that's it.

[speedaddictM3]

Originally Posted by aussiem3

Although there is valid argument to change to 0w-40, until such time BMW sends out a SB, I don't think it's advisable to change the oil. There is a reason why 10w-60 was used in the first place. The car was tested in all sorts of weather conditions - both hot ands cold, and regularly driven at high speed, and now based on a web page you are prepared to change the oil. Although there are merits I think you are leaving yourselves open to BMW turning down any claim one might have against an engine failure. I am just putting this out. Think twice before you change. I have nothing to gain form you using either of these oils. What's important is a healthy motor that we can enjoy rather than worry.

Originally Posted by Cool Steel

Agreed 100% ...and exactly what I mentioned 17 posts ago.

This thread is geared more towards those who are out of warranty or will keep the car beyond warranty. If you're one of those who lease a new car for 2 years then dump it by all means keep using TWS and change it once a year. If worst case scenario happens.and you blow an engine the warranty will fix it.

[chris719]

I would also consider that BMW only uses Castrol oils due to a deal with Castrol. They might consider TWS the "most suitable" Castrol product.

The 911 GT3 comes from the factory with M1 0w-40, and that is a very high RPM engine designed for track use.

From Blackstone Labs UOA it can be seen that TWS shears down to a 40 quickly anyway. If I was under warranty I would run TWS to avoid issues though.

[regular guy]

I just checked the journal measurements of the factory and aftermarket cranks we measured. I have the full set of main journal measurements on the aftermarket crank, but I don't have the full set of connecting rod measurements. But I do have the max and min rod journal sizes on the aftermarket crank.

Factory main journals: 2.36142 +/- 0.00018"
Factory rod journals: 2.04655 +/- 0.00005"

Aftermarket main jouernals: 2.36115 +/- 0.00005"
Aftermarket rod journals: 2.04720 +/- 0.00005"

The mains factory vs. aftermarket mains differ by 0.00013" and the rods differ by 0.00065" -- I'm not sure if this is due to temperature differences or not; and I'm not even sure how significant this is. I will assume it's due to temperature differences because when we measured the two crankshafts side by side on the same day (see discussion in post #2 of "Connecting Rod Side Clearance Issues"), we measured the journals identical to each other. I do notice the journal variance is much worse on the factory crank mains than it is on the aftermarket crank.

[aussiem3]

Originally Posted by chris719

From Blackstone Labs UOA it can be seen that TWS shears down to a 40 quickly anyway. If I was under warranty I would run TWS to avoid issues though.

What does 0w-40 shear to?

[Yellow Snow]

Originally Posted by regular guy

I just checked the journal measurements of the factory and aftermarket cranks we measured. I have the full set of main journal measurements on the aftermarket crank, but I don't have the full set of connecting rod measurements. But I do have the max and min rod journal sizes on the aftermarket crank.

Factory main journals: 2.36142 +/- 0.00018"
Factory rod journals: 2.04655 +/- 0.00005"

Aftermarket main jouernals: 2.36115 +/- 0.00005"
Aftermarket rod journals: 2.04720 +/- 0.00005"

The mains factory vs. aftermarket mains differ by 0.00013" and the rods differ by 0.00065" -- I'm not sure if this is due to temperature differences or not; and I'm not even sure how significant this is. I will assume it's due to temperature differences because when we measured the two crankshafts side by side on the same day (see discussion in post #2 of "Connecting Rod Side Clearance Issues"), we measured the journals identical to each other. I do notice the journal variance is much worse on the factory crank mains than it is on the aftermarket crank.

So the Carillo rods are a couple of tenths tighter than oem and the Stroker crank is around 6 tenths bigger than oem?

This will reduce clearance by almost a thou! (.0008").

You say the bearings look ok apart from the distortion at the parting line which is down to Carillo.

If these bearings were ok after 24k miles of supercharged use with .0008" less clearance than standard, why would you still think that oem clearance would cause a problem?

[chris719]

Originally Posted by aussiem3

What does 0w-40 shear to?

Not sure off the top of my head, but I seem to remember from the BITOG forum that it ended up closer to where it started than the TWS. I think the rule of thumb is the larger spread in viscosity means less shear stability in general.

Unless you track the car I doubt the high temp viscosity / HTHS of M1 0w-40 is too low, and even then probably not.

[SenorFunkyPants]

Originally Posted by regular guy

I noticed that what you said above doesn't seem to match the contents of that article too well -- at least not the way you said it here. It's like you substituted your own set of comments and tried to put them in quotes to make them look like the originals but removed parts of them to alter the overall meaning.

Lets see, on Carrillo rod cap deformation I wrote:
Firstly in the original stroker build log: in "3 or 4" of the original Carrillo rods, "the connecting rod cap had deformed, becoming oval shape pinching the connecting rod bearings. Pinching the bearings was causing them wear down to the copper in this location"
You wrote: (Direct quote M3forum thread)
"the connecting rod cap was deforming, becoming oval shape, and pinching the connecting rod bearings. Pinching the bearings was causing them wear down to the copper in this location"
I left out the following (which is a prelude to the above) because of repetition or are a given apart from "three or four":
"On three or four of the connecting rods, precisely where the connecting rod cap bolts together, three or four of the bearings were worn to the copper. At such high power and high rotational velocity (high RPMs)"
[1]

On side clearance I wrote:
Secondly the second custom set from Carrillo had measurable width variance, enough that they had to be selectively machined to produce the desired side clearance.
Which was paraphrased from: (Direct quote M3forum thread)
"Even though Carrillo connecting rods are made to the highest standards, we did find a few of them were 1/2 of a thousanth of an inch different than the others (0.0005"). Since Van Dyne already planned to use his own tolerance specifications, this was our opportunity to make the necessary corrections."

Note also that the first set of Carrillo rods also showed poor side clearance tolerance....
from page one this thread: (Direct quote)
" Van Dyne grabbed our spare set of Carrillo rods that had been in the motor previously. He grabbed them as if he expected to find evidence of possible damage. Within a split second, Van Dyne pointed to the side of the Carrillo rod and said: See that tiny blue spot? That's caused by heat from these two rods rubbing together because they are so tight. See that scrape mark? That's also caused by these two rods rubbing together."

On fitting I wrote:
Thirdly Carrillo rods have there own rod bolts, torque specifications and thread/head lubricant.
Which was paraphrased from page one this thread: (Direct quote)
"Carrillo rod bolts are different, we made sure to follow the Carrillo torque specifications and use the exact thread/head lubricant they recommended."

So as I wrote:
"They [Carrillo rods] have poor manufacturing consistency, distortion in use and employ a different bolts/torque/lubricant"
it is completed substantiated by words directly quoted from your posts.
I don't see any intellectual dishonesty in what I wrote or the way it was presented but I will be more careful with quoting in future.....Anyway, leaving aside the fact that Carrillo rods are indeed totally unsuitable as an indicator for issues with BMW OEM rods...its the last part which is clearly the most relevant and which gets totally ignored:

The ONE single measurement made with an OEM BMW rod, crankshaft and a new OEM BMW bearing gave a clearance of .0014" The minimum Cevite "Recommended clearance for rods (52mm journal) is 0.00153"

A measurement that would have grabbed the attention of even a junior high school kid investigating the phenomenon with any kind of scientific rigor, was dismissed. Honestly didn't you think that this was worth further investigation seeing as how it puts a massive hole in "Truth #1":
"There is a long standing clearance-to-journal ratio best practice rule that factory and racing engine builders alike have followed for 50+ years. [...] The S65 engine cuts that clearance ratio in half. (1, 2)".
But in reality is less like 50% and more like 9%.

Note also truth #3 (a vague undefined side clearance ratio) is only supported by the poor side clearance tolerances of Carrillo rods. No tests of BMW OEM rods that I could find.

EDIT [1] On reflection I suppose its possible that a casual viewer might think that I was trying to infer that the wear was on the bearing surface rather than at the parting line. However the parting line wear had already been noted and photographed on the first page of the thread, specifically pointed out later in the thread again with photos and shown clearly in the M3post thread also with photos....so I assumed it was a given. Not that it really matters the point was always about the rod cap distortion.

[aussiem3]

Originally Posted by chris719

Not sure off the top of my head, but I seem to remember from the BITOG forum that it ended up closer to where it started than the TWS. I think the rule of thumb is the larger spread in viscosity means less shear stability in general.

Unless you track the car I doubt the high temp viscosity / HTHS of M1 0w-40 is too low, and even then probably not.

My wife's X3 diesel nudges 100 Celsius on 5w-30 everyday I drive it to work. I don't track my m3 but what I'm worried about the overall load on the oil given how harsh and unforgiving our summer can be. Also 0w-40 is very expensive here.

[gatorfast]

Originally Posted by chris719

I would also consider that BMW only uses Castrol oils due to a deal with Castrol. They might consider TWS the "most suitable" Castrol product.

The 911 GT3 comes from the factory with M1 0w-40, and that is a very high RPM engine designed for track use.

From Blackstone Labs UOA it can be seen that TWS shears down to a 40 quickly anyway. If I was under warranty I would run TWS to avoid issues though.

If you read more about the history of TWS you would know it was co-developed with M engineers specifically for M engines. Pretty sure any major oil brand would want to partner with BMW so surely Castrol does not control their relationship.

Also, I have read multiple times that TWS shears to a 40 but my last (and only) UOA showed viscosity was at a 50wt after 8k miles

As for warranty issues, the new BMW oil recommendations states all LL01 oils are approved for the S65 meaning the M1 0-40 is perfectly fine to use.

[SenorFunkyPants]

Originally Posted by gatorfast

As for warranty issues, the new BMW oil recommendations states all LL01 oils are approved for the S65 meaning the M1 0-40 is perfectly fine to use.

I guess this is on a per-market basis. Next time I'm in my dealer I'll ask but I don't think this recommendation yet applies to the UK market and therefore by extension to other markets.
Plus the new oil recommendations seem very ambiguous....if you are still in warranty I would stick with whatever oil your dealer has on his list as recommended for the M3 when they do the oil change....if it all goes tits up at least they can't catch you out on it.

[Gearhead999s]

Originally Posted by SenorFunkyPants

I guess this is on a per-market basis. Next time I'm in my dealer I'll ask but I don't think this recommendation yet applies to the UK market and therefore by extension to other markets.
Plus the new oil recommendations seem very ambiguous....if you are still in warranty I would stick with whatever oil your dealer has on his list as recommended for the M3 when they do the oil change....if it all goes tits up at least they can't catch you out on it.

I checked with my dealer and in Canada the only approved oil is the Castrol 10 w 60 and he did check for any recent revisions.

[kawasaki00]

Originally Posted by aussiem3

Although there is valid argument to change to 0w-40, until such time BMW sends out a SB, I don't think it's advisable to change the oil. There is a reason why 10w-60 was used in the first place. The car was tested in all sorts of weather conditions - both hot ands cold, and regularly driven at high speed, and now based on a web page you are prepared to change the oil. Although there are merits I think you are leaving yourselves open to BMW turning down any claim one might have against an engine failure. I am just putting this out. Think twice before you change. I have nothing to gain form you using either of these oils. What's important is a healthy motor that we can enjoy rather than worry.

Originally Posted by Cool Steel

Agreed 100% ...and exactly what I mentioned 17 posts ago.

For you down under guys this might be the case but here in the states there is a SB and the website says it and the dealership is giving a choice now as to what you want.
Obviously different countrys are recommending different oil but you need to state that instead of a blanket statement that tells everyone they are running a non approved oil when in fact they are.

[kawasaki00]

Originally Posted by Yellow Snow

So the Carillo rods are a couple of tenths tighter than oem and the Stroker crank is around 6 tenths bigger than oem?

This will reduce clearance by almost a thou! (.0008").

You say the bearings look ok apart from the distortion at the parting line which is down to Carillo.

If these bearings were ok after 24k miles of supercharged use with .0008" less clearance than standard, why would you still think that oem clearance would cause a problem?

Something must be amiss, it is impossible to run a rod at 1/2 thou clearance.

[chris719]

Originally Posted by gatorfast

If you read more about the history of TWS you would know it was co-developed with M engineers specifically for M engines. Pretty sure any major oil brand would want to partner with BMW so surely Castrol does not control their relationship.

Also, I have read multiple times that TWS shears to a 40 but my last (and only) UOA showed viscosity was at a 50wt after 8k miles

As for warranty issues, the new BMW oil recommendations states all LL01 oils are approved for the S65 meaning the M1 0-40 is perfectly fine to use.

Actually if you read the non BMW marketing history of TWS you would see that it started life as a race oil non BMW specific, Syntec Formula RS 10w-60. BMW Motorsport liked it and paid them to rebrand it TWS when they discontinued the original product.

It was so intimately designed with M engineers that S62 and S54 did not even spec it originally...

[chris719]

Originally Posted by aussiem3

My wife's X3 diesel nudges 100 Celsius on 5w-30 everyday I drive it to work. I don't track my m3 but what I'm worried about the overall load on the oil given how harsh and unforgiving our summer can be. Also 0w-40 is very expensive here.

100C is normal? The oil is fine for 911 GT3 9000 rpm and Nissan GT-R in all markets.

[kawasaki00]

Regular Guy sent me a complete set of rods bearings and pistons to document out of a STOCK engine.
The purpose of this post is to address the detonation. What was found is that there is no significant detonation leading to bearing wear on this engine. Not saying some engines may not have it but this engine does not.
The first two pictures are reference from another type of engine that has too much timing and detonation. The shiny spots on the rod and silver specs on the back of the bearings are what happens to a rod bearing when it is moving around in the rod under load. The bearing actually lifts off the rod, oil gets behind it and then when it is slammed back down again this is what causes the silver specs from fretting. You can see the picture of the complete set of rods that the oil stain has not penetrated the back side of the bearing and discolored the rod. This means that at no time has the rod bearing deformed to the point that is lifts out of the rod itself. The back of the rod bearing also shows the same thing, there is also no fretting on the back of the bearing.
The first place that detonation will show up is in the pin bore of the piston and the bushing of the rod.
There is no evidence of heat in the pin bores nor rainbow effect in the bushings. What I have circled on the rod pinbore is the area where when the engine is detonating it will beat the brass out the side like mushing the filling out of a doughnut. There is nothing to show this engine has been detonating to the point that is would cause any type of rod bearing wear.

As far as the piston tops, well they have alot of build up. This can be from one of two things, too much blowby due to loose rings or on a street engine from the emission system dumping oil back into the intake side. Without having the entire engine to look at it is hard to say. I have noticed in the past that certain oils also do this. I wont place judjment on that as that will certainly erupt a brand war on here.
The second ring shows very good seal as it is only worn about 1/4 of the ring. When there is poor sealing that second ring will wear all the way across the face.
In conclusion there is no detonation in this engine. Failure analysis and teardown documentation is something we do regularly. The findings are conclusive with other people and they are what they are to put it into a nutshell.
In the next couple days i will post the specs from the older rod bearings and will also post the numbers from a fresh set of bearings that are fit up ready to run.

[swartzentruber]

Originally Posted by kawasaki00

For you down under guys this might be the case but here in the states there is a SB and the website says it and the dealership is giving a choice now as to what you want.
Obviously different countrys are recommending different oil but you need to state that instead of a blanket statement that tells everyone they are running a non approved oil when in fact they are.

Kawasaki is correct, BMW NA has changed the approved oils to either the TWS 10W-60, a specific Castrol 5W-30, or LL-01 spec oil, of which Mobil1 0W-40 is on the list. It appears other markets outside the US have retained the TWS 10W-60 only approval. This is both documented on the BMW NA website, and I've also seen with my own eyes a little brochure that has been sent out to the BWM service advisers about it (the change in recommendation for M engines), though I didn't take any pictures so some people still don't believe it. I don't think anyone in the NA market needs to be worried about warranty coverage running the M1 10W-40, and yes I'm planning to switch to that at my next oil change.

[oldmanstyle]

Originally Posted by swamp2

If you don't recognize proper debate and proper evidence I guess too bad.

Hey guy, I'm a practicing structural engineer with BS and MS degrees from a school that was #2 in the nation in the field at the time of my graduation. I graduated both times with highest honors and have been practicing in this highly technical field for over a decade now. Be careful what you assume about my thought processes.

[SenorFunkyPants]

Originally Posted by kawasaki00

Regular Guy sent me a complete set of rods bearings and pistons to document out of a STOCK engine.
The purpose of this post is to address the detonation. What was found is that there is no significant detonation leading to bearing wear on this engine.

The problem is that as soon as you use the word detonation, most people immediately think of the extreme end of the spectrum, pistons with holes in them etc. Also interesting that the rod bearing photos from a stock engine showing high wear from this thread page 1 that I sent to Clevite were diagnosed as being caused by detonation.
Given that with the M3's ionic current system, the ECU holds the combustion at the edge of detonation when using fuel with insufficient anti knock qualities to allow it to reach its target timing advance.
And that it is my understanding from posts regarding S65 M3 ECU tuning that the minimum octane that the stock ECU is calibrated to adjust for is 90 Aki.
What would do you think be the effect of running 87 octane in this environment?
Would it be unreasonable to assert that in this case the combustion process might produce elevated cylinder pressures?