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      11-15-2013, 10:07 AM   #903
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Originally Posted by Yellow Snow View Post
Do you find the shell 99 to be better than Tesco 99?
I've tended to go with the Tesco 99 because of the very high turnover that the station has...the shell station being more expensive tends to be far less busy.
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      11-15-2013, 10:23 AM   #904
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Quote:
Originally Posted by Cool Steel View Post
Assumes that although there is no detonation signs on piston tops etc. ... that there is enough detonation to cause lower bearing damage but not upper piston top damage? What...?
I wanna believe...but this seems like a bit of a stretch.
The analysis by Mahle is perfectly credible. The bottom bearings shows none of the accelerated wear that the top bearings do. The wear pattern on the top bearing strongly points to wear caused during the combustion stroke.
If you look at the wear shown in:
Discovering S65 Bearing Issue post #2 you will see the beginning of accelerated wear offset to one side on the top bearing shell - this is entirely conducive with wear created only during the combustion stroke event. The same peak wear with a similar offset in the top bearing is indicated in several of the other photos shown by the OP at the beginning of the thread.

As I wrote earlier:
"[...]there must be a threshold level of vertical downward force exerted by the rod bearing shell on the crankshaft journal during the combustion stroke below which the oil film remains intact and no wear occurs. By design this threshold should not be expected to be exceeded during the normal function of a standard engine running the recommended oil and fuel."

I think its perfectly credible that the S65 run as designed does not produce excessive bearing wear. Firstly because the overall failure rate is so low and secondly because supercharged S65s with the standard bearing manage to last more than 5 mins without throwing their rods at the countryside.

The S65 failure rate points strongly at the market (Ca) with the lowest average fuel octane ratings (91-87) with a high ambient temperature and low humidity. Conversely the UK market with a high average octane rating (95-91) and cooler wetter weather has no known reported failures.
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      11-15-2013, 11:00 AM   #905
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Quote:
Originally Posted by speedaddictM3 View Post
Still no one is explaining why crappy gas is not ruining bearings on other high performance engines. Why only the M3 and M5?
Can't really comment...don't have any data and it would take a lot of time to research it.
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      11-15-2013, 11:03 AM   #906
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Originally Posted by speedaddictM3 View Post
totally agree with that. The M3 isn't good or special enough to justify all the hassle and headaches. I hope to get rid of mine and get a vette or gtr instead.


Still no one is explaining why crappy gas is not ruining bearings on other high performance engines. Why only the M3 and M5? Even if detonation is a contributing factor I still believe regular guy's theory that too tight clearance and too thick an engine oil are the biggest culprits.

There are many factors that pose a risk to detonation I gather. The m3/m5 seem to have an awfully high compression ratio of 12:1 which is higher than prior Ferraris until the 458. Someone can chime in but there are loads of factors effecting detonation risk. The other thing that appears to be a unique character to the m3/m5 vs other cars is the ion sensing knock system. Or, the knock system is good but not as good as they thought and they set their timing targets too aggressively thinking the ion knock would be more able to take timing to the limit than conventional, but perhaps in real world does not perform quite as well.

So potentially running higher octane like 93 and perhaps a tune from aftermarket to lower max timing targets by a couple degrees, especially if running 91 could be something to market?

I was interested to hear the local experts Kawasaki, BMRLVR, regular guy etc however seems their entire theory was incorrect but I think we all thank them and everyone for so much great data and great work.

I have looked at probably 50 pictures online comparing detonation vs oil starvation and almost always there is no random cavitation or such a spread of wear on oil starved bearings unless the wear occurs on the bearings seeing the least oil/ have least clearance. Plus the pattern if anyone looks at enough pictures you see the answer is clearly detonation. Given the bearings with the most clearance have the most wear in some people's cases on the m3, that is the most definitive evidence that less clearance is perhaps actually protective to detonation on these engines if anything, although not sure how that would work!
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      11-15-2013, 11:12 AM   #907
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Quote:
Originally Posted by SenorFunkyPants View Post
Can't really comment...don't have any data and it would take a lot of time to research it.
So you have time to comment about theories all day, but you don't have time to do some research to help validate your theory? The words escape me
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      11-15-2013, 11:13 AM   #908
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Quote:
Originally Posted by Thebrain View Post
Question to swamp: Would it not be prudent to stick with 10w60 since we now know detonation is most likely the main cause of this bearing wear? Using a thinner oil would create even less of a cushion I assume? Thus detonation will have even more of an impact on cars running thinner oil. Any thoughts Mr. Swamp?
I am not changing oil when I am under warranty until BMW comes out with a direct statement saying that they are recommending a change. A change that mysteriously shows up on their web page is not going to cut it.
Why? because BMW needs a reason to blame YOU. Your engine blows up and they will ask you why didn't you take your service managers recommendation of 10-60?? ( you know your service manager is not going to recommend the lower viscosity because these guys don't know crap). My service manager thought the star on the side of the sidewall meant it was a run flat.

The lower viscosity makes sense but is it a guaranteed savior of the engine? No one has proved that it is.
However, the only guaranteed savior of your engine is sticking to BMWs guidelines and your service drones recommendations, and then making them change your engine out under warranty when it blows and you show them that you did everything that they told you to.

Last edited by Cool Steel; 11-15-2013 at 11:28 AM.
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      11-15-2013, 11:16 AM   #909
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Quote:
Originally Posted by Thebrain View Post
There are many factors that pose a risk to detonation I gather. The m3/m5 seem to have an awfully high compression ratio of 12:1 which is higher than prior Ferraris until the 458. Someone can chime in but there are loads of factors effecting detonation risk. The other thing that appears to be a unique character to the m3/m5 vs other cars is the ion sensing knock system. Or, the knock system is good but not as good as they thought and they set their timing targets too aggressively thinking the ion knock would be more able to take timing to the limit than conventional, but perhaps in real world does not perform quite as well.

So potentially running higher octane like 93 and perhaps a tune from aftermarket to lower max timing targets by a couple degrees, especially if running 91 could be something to market?

I was interested to hear the local experts Kawasaki, BMRLVR, regular guy etc however seems their entire theory was incorrect but I think we all thank them and everyone for so much great data and great work.

I have looked at probably 50 pictures online comparing detonation vs oil starvation and almost always there is no random cavitation or such a spread of wear on oil starved bearings unless the wear occurs on the bearings seeing the least oil/ have least clearance. Plus the pattern if anyone looks at enough pictures you see the answer is clearly detonation. Given the bearings with the most clearance have the most wear in some people's cases on the m3, that is the most definitive evidence that less clearance is perhaps actually protective to detonation on these engines if anything, although not sure how that would work!
I see we have a new member that knows way more than the rest of us.
So we have a theory and pictures and years of experience yet you tell us we are all wrong and dont know what we are talkng about.
Yet you do the same thing saying you have looked at pictures on the internet and listened to others and now you are correct.
Dont you see the irony.
Once again I will state.... There have been rod bearing failures in our area where 93 is available and a scan of the computer can see ignition and fuel trims so the dealer knows what gas has been in it. The failures are not just in California
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      11-15-2013, 11:23 AM   #910
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Quote:
Originally Posted by kawasaki00 View Post
There have been rod bearing failures in our area where 93 is available and a scan of the computer can see ignition and fuel trims so the dealer knows what gas has been in it. The failures are not just in California
You should change your signature to that so you can stop repeating it *lol*
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      11-15-2013, 11:30 AM   #911
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Quote:
Originally Posted by whats77inaname View Post
So you have time to comment about theories all day, but you don't have time to do some research to help validate your theory? The words escape me
Heh you got me...excuse me for a week or two while I head off on this wild goose chase.
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      11-15-2013, 11:33 AM   #912
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Quote:
Originally Posted by kawasaki00 View Post
I see we have a new member that knows way more than the rest of us.
So we have a theory and pictures and years of experience yet you tell us we are all wrong and dont know what we are talkng about.
Yet you do the same thing saying you have looked at pictures on the internet and listened to others and now you are correct.
Dont you see the irony.
Once again I will state.... There have been rod bearing failures in our area where 93 is available and a scan of the computer can see ignition and fuel trims so the dealer knows what gas has been in it. The failures are not just in California


but you know it all, cause you listed your "credentials"




This whole board needs to relax.

Again, what page is this up to.... 42!!! ???


How many M cars have blown up ??



Where are the numbers??
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      11-15-2013, 11:36 AM   #913
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Quote:
Originally Posted by kawasaki00 View Post
I see we have a new member that knows way more than the rest of us.
So we have a theory and pictures and years of experience yet you tell us we are all wrong and dont know what we are talkng about.
Yet you do the same thing saying you have looked at pictures on the internet and listened to others and now you are correct.
Dont you see the irony.
Once again I will state.... There have been rod bearing failures in our area where 93 is available and a scan of the computer can see ignition and fuel trims so the dealer knows what gas has been in it. The failures are not just in California
I know everyone wants to embrace this new easy fix, and BMW yay is still awesome. I don't buy it...

However, Kawasaki, I respect your opinion and all the work you and regular guy did on this...I am wondering and maybe I missed this but wouldn't there be detonation damage to a piston top if this was the "real" problem...am I missing the pictures that prove the detonation with piston damage?
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      11-15-2013, 11:36 AM   #914
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Quote:
Originally Posted by Yellow Snow
How does the size between the parting lines compare to a regular lower revving BMW motor such as an M54?

The S65 shells only give a .0016" clearance across the smallest point ie 90 degrees to part line. The clearance across the part line is at least .002" greater, thus giving an oval bore with .0035" - .004"clearance at the widest point.

From this I'm assuming that BMW did some stress analysis at 8,400rpm and found the rod bore stretched by .001". This would mean the bearing bore would be perfectly round at 8,400rpm resulting in a clearance of approx .0025" all around the bearing?
Good question!
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      11-15-2013, 11:38 AM   #915
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Quote:
Originally Posted by Cool Steel View Post
I know everyone wants to embrace this new easy fix, and BMW yay is still awesome. I don't buy it...

However, Kawasaki, I respect your opinion and all the work you and regular guy did on this...I am wondering and maybe I missed this but wouldn't their be detonation damage to a piston top if this was the "real" problem...am I missing the pictures that prove the detonation with piston damage?


yes a simple search will show you what a piston will look like that has experienced pre-ignition or detonation versus one running fine
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      11-15-2013, 11:39 AM   #916
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Quote:
Originally Posted by whats77inaname View Post
You should change your signature to that so you can stop repeating it *lol*
Yea I know right LOL
Some need to understand how compression rato works. We will never know how the management system interacts unless a combustion system is hooked up and that is not going to happen. The compression ratio doesnt mean crap unless you know all the other variables such as cc volume of the head, dish of the piston and other things such as cam timing. The bore and stroke have an effect on overall compression and how it equates to the real ratio.
The LS7 chevy engine is a 4.125 bore and 4 inch stroke. Making 475ft/lb with 11:1 compression and they require 91 minimum octane. The smaller bore and stroke of the s65 plays a roll in the compression ratio, one cant just say "12:1 is too high for a street motor"
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      11-15-2013, 11:49 AM   #917
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Quote:
Originally Posted by kawasaki00 View Post
The smaller bore and stroke of the s65 plays a roll in the compression ratio, one cant just say "12:1 is too high for a street motor"
In the B-series Honda engine we built, by using the B18C block w/the B16A head, along with B18C rods and JDM Civic Type R pistons, we were running 12.5:1 CR. It had a Toda B spec head package (Toda B spec cams, dual valve springs) and Ti retainers. The redline was set to 9K, and it ran just fine for 10s of thousands of miles. Parted it and sold it to move on to other things, but the CR never gave me a problem, and the car was my daily, and yeah, it only saw 93 octane.

Quote:
Originally Posted by Cool Steel View Post
I am wondering and maybe I missed this but wouldn't there be detonation damage to a piston top if this was the "real" problem...am I missing the pictures that prove the detonation with piston damage?
The tops, and the ring lands, yes. Blow by will increase as the rings start to fail, as well. The easiest and least expensive way to see detonation is to PULL THE SPARK PLUGS.

There are plenty of sites that go into detail about reading spark plugs. This is just one: http://www.theultralight**********/sparkplugs.htm

Edit: I don't know *why* that is blocked but the site is theultralightplace dot com, followed by the rest...

Last edited by whats77inaname; 11-15-2013 at 12:01 PM.
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      11-15-2013, 11:49 AM   #918
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Quote:
Originally Posted by Thebrain View Post
I was interested to hear the local experts Kawasaki, BMRLVR, regular guy etc however seems their entire theory was incorrect but I think we all thank them and everyone for so much great data and great work.
Plus the pattern if anyone looks at enough pictures you see the answer is clearly detonation.
[quote=hughs65e90;14979173]but you know it all, cause you listed your "credentials"
QUOTE]

No, you are reading between the lines. I have never made such statement that I know everything, furthermore listing credentials is important to those who want to know who is doing the talking and not some putz that pushes pencils for a living.
Like I said, he tells us we are wrong, that is his opinion so that is fine but then he says that the answer is clearly detonation.
Yet none of the top rings, pin bores or small ends of the rods show anything damaging. If the engine was detonating so bad that it beat the rod bearing out of it the top ring would show obvious micro welding. Most people dont even know what that is or what it looks like, and that is fine. I am sure there is some knock going on, every single street car has knock but not to the point that the rod bearing gets beat out and throws the rod out.
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      11-15-2013, 11:52 AM   #919
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As far as the california fuel goes, there's a 2011 with 60K on it that has 0 lead wear and 1ppm of tin, and does not go above 3K rpm until it's up to temperature when using TWS. I'm not sure if that's due to the newer bearing or proper care of the motor.

Question - If detonation is happening and causing bearing damage, is it possible it's significant enough to starve the bearing to the point where the metal-metal contact overheats the bearing and discolors the rods as pictures in a previous post?

In the Gintani video, it appears the middle main bearings and last (4&8) rod bearings were destroyed from a claimed oil starvation. Are these last last in line of the oiling system? Do these cars have oiling issues when tracked?

Quote:
Originally Posted by BMRLVR View Post
True enough, but the F20C didn't have nearly as flat a torque curve of the S65. The flat torque curve is a result of the VANOS and very aggressive ignition timing control. Such aggressive timing control in fact that by adding higher octane fuel nets gains of upto 30 RWHP on a dyno.
F20's do have a very flat torque curve on both cam lobes. There's some drop-off in the last ~700rpm of its 9000rpm redline but overall it's impressively flat for such a high redline.
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      11-15-2013, 11:52 AM   #920
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Quote:
Originally Posted by hughs65e90 View Post
yes a simple search will show you what a piston will look like that has experienced pre-ignition or detonation versus one running fine
Yes, I understand what one looks like, that was not my question.
I wanted to know if the BMW M3s with the bearing problems that went boom...had piston top damage.
Not what it looks like...lol

I am sure that regular guy and all the others that contributed to this thread looked not only at the bearings/connecting rods but also at piston tops correct? I am sure they found no detonation signs on these tops...

That was my question...

And whoops here is my answer:


Quote:

Yet none of the top rings, pin bores or small ends of the rods show anything damaging. If the engine was detonating so bad that it beat the rod bearing out of it the top ring would show obvious micro welding. Most people dont even know what that is or what it looks like, and that is fine. I am sure there is some knock going on, every single street car has knock but not to the point that the rod bearing gets beat out and throws the rod out.
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Last edited by Cool Steel; 11-15-2013 at 12:02 PM.
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      11-15-2013, 11:54 AM   #921
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Quote:
Originally Posted by whats77inaname View Post
In the B-series Honda engine we built, by using the B18C block w/the B16A head, along with B18C rods and JDM Civic Type R pistons, we were running 12.5:1 CR. It had a Toda B spec head package (Toda B spec cams, dual valve springs) and Ti retainers. The redline was set to 9K, and it ran just fine for 10s of thousands of miles. Parted it and sold it to move on to other things, but the CR never gave me a problem, and the car was my daily, and yeah, it only saw 93 octane.



The tops, and the ring lands, yes. Blow by will increase as the rings start to fail, as well. The easiest and least expensive way to see detonation is to PULL THE SPARK PLUGS.
I agree on this one. This is a totally different topic but I have never understood why guys that have a blower continue to run the stock plug. One should always run a colder plug in a boosted car. Maybe they are not available.. I am not sure.
Unfortunately there are few people that can read spark plugs correctly with unleaded fuel, it is also hard to do in a street car as idleing messes it up. Clean cut is the best but is hard to do.
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      11-15-2013, 11:58 AM   #922
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Quote:
Originally Posted by kawasaki00 View Post
I agree on this one. This is a totally different topic but I have never understood why guys that have a blower continue to run the stock plug. One should always run a colder plug in a boosted car. Maybe they are not available.. I am not sure.

no offense but this I where I question you.. Yes colder plugs are avail and I would not say an absolute, YES< run colder plugs under boost.

These f@ckin cars need to be datalogged first and foremost to see if there is knock and if the car is pulling timing than yes a switch to a cooler plug may suffice but dependent upon many variables it shouldn't be an absolute. It prob would benefit a handful of cars on here though. I for one can't believe people run 9 lbs on a 12:1 motor but that's just me. If it were me I would be running 20+ lbs on a built 9 or 10:1 piece.


People are just throwiing parts and things around on these canned tunes. I'm suprised not more SC cars have not blown up
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      11-15-2013, 11:59 AM   #923
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It shouldn't be too hard to read a plug either
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      11-15-2013, 12:02 PM   #924
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Quote:
Originally Posted by kawasaki00 View Post
Unfortunately there are few people that can read spark plugs correctly with unleaded fuel, it is also hard to do in a street car as idleing messes it up. Clean cut is the best but is hard to do.
Quote:
Originally Posted by hughs65e90 View Post
It shouldn't be too hard to read a plug either
I agree, and I don't see why it isn't done more often.


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