BMW M3 Forum (E90 E92)

BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read


Go Back   M3Post - BMW M3 Forum > E90/E92 M3 Technical Topics > Engine, Transmission, Exhaust, Drivetrain, ECU Software Modifications
 
Mporium BMW
Post Reply
 
Thread Tools Search this Thread
      01-30-2024, 12:33 PM   #2971
Assimilator1
Major
Assimilator1's Avatar
United Kingdom
587
Rep
1,024
Posts

Drives: BMW M3 e92 08 & 330d e90 10
Join Date: Sep 2019
Location: UK, Surrey

iTrader: (0)

Garage List
2010 BMW 330d  [8.00]
2008 BMW M3  [0.00]
Quote:
Originally Posted by RSV Atelier View Post
....

All are ok , and all measured 0.51 with the new bearings.
I just want to say , i am not a "professional garage " . It is something that i do in my spare time .
Have you got a photo of your old bearings?

Quote:
Originally Posted by higgins2613 View Post
2013 with 45600 miles. Replaced with ACL and ARP2000’s.
Fancy carrying out a little experiment on 1 or 2 of your old shells?
__________________
Appreciate 0
      02-07-2024, 05:07 PM   #2972
Stevenglan
New Member
12
Rep
8
Posts

Drives: 2008 BMW M3 (E93)
Join Date: Feb 2024
Location: Cincinnati, OH

iTrader: (0)

2008 E93 M3 with 156,522 Miles (Daily Driver)

2008 E93 M3 with 156,522 Miles (Factory Bearings)

The car has always been on a 5K mile OCI using factory BMW 10W60 oil change kits. No damage to the crank considering the condition.

I replaced them with ACL Custom Clearance Rod Bearings and ARP2000 Bolts

Name:  IMG_9671.jpeg
Views: 395
Size:  150.3 KB

Name:  IMG_9672.jpeg
Views: 390
Size:  198.2 KB

Name:  IMG_9675.jpeg
Views: 378
Size:  144.6 KB

Name:  IMG_9676.jpeg
Views: 387
Size:  167.5 KB

Name:  IMG_9677.jpeg
Views: 383
Size:  160.5 KB

Name:  IMG_9678.jpeg
Views: 389
Size:  133.7 KB
Appreciate 3
      02-07-2024, 05:41 PM   #2973
DrFerry
Field Marshal
DrFerry's Avatar
United_States
6726
Rep
1,833
Posts

Drives: '08 E92 M3
Join Date: Jul 2010
Location: Greenville, SC

iTrader: (5)

Garage List
2008 BMW M3  [5.25]
2015 BMW X5  [4.50]
Quote:
Originally Posted by Stevenglan View Post
2008 E93 M3 with 156,522 Miles (Factory Bearings). The car has always been on a 5K mile OCI using factory BMW 10W60 oil change kits. No damage to the crank considering the condition.
I replaced them with ACL Custom Clearance Rod Bearings and ARP2000 Bolts
It was definitely time. You can sleep better now. I'm interested to know what ACL Custom Clearances you went with?
.
Attached Images
 
__________________
'08 E92 M3 DCT Melbourne Red/Bamboo Beige Leather/EDC/SSP Spec-R DCT clutch discs/SSP Pro-Gold DCT Fluid/Quaife LSD/3:45 Final Drive by Diffs Online/BE Bearings & ARP Bolts/Vibra Technics Engine Mounts/M3 World HFC X-Pipe/LUX H8 180/BPM Sport DCT Tune/PFC Z-Rated Pads/ECS Brass Brake Caliper Bushings/Alex Shop Solid Sub-frame Bushings/Motul 600/Tint
Appreciate 2
      02-07-2024, 06:16 PM   #2974
Stevenglan
New Member
12
Rep
8
Posts

Drives: 2008 BMW M3 (E93)
Join Date: Feb 2024
Location: Cincinnati, OH

iTrader: (0)

It was! I can definitely sleep better now haha. Here is the link to the set that I put in:

https://europowermotorsports.com/pro...-mixed-shells/

They created their own customized set that will achieve .0023″ to .0025″ bearing clearance, similar to the BE Bearings. Mine measured a little under .0025" on all journals with plastigague. It was right at $490 with bolts.
Appreciate 2
DrFerry6725.50
      02-07-2024, 11:34 PM   #2975
0-60Motorsports
Brigadier General
0-60Motorsports's Avatar
Bahrain
788
Rep
3,151
Posts

Drives: BMW M3 JB 04 Coupe
Join Date: Aug 2007
Location: Kingdom of Bahrain

iTrader: (1)

Quote:
Originally Posted by Stevenglan View Post
It was! I can definitely sleep better now haha. Here is the link to the set that I put in:

https://europowermotorsports.com/pro...-mixed-shells/

They created their own customized set that will achieve .0023″ to .0025″ bearing clearance, similar to the BE Bearings. Mine measured a little under .0025" on all journals with plastigague. It was right at $490 with bolts.
Excellent price. Thanks for posting that.
__________________
Current Mods:
2004 E46 M3cs JB/CSL
2010 E70 X5M AW/BLACK
2011 VW Golf R DSG White/Black
IG: @060Motorsports
Appreciate 1
DrFerry6725.50
      02-08-2024, 01:11 PM   #2976
Assimilator1
Major
Assimilator1's Avatar
United Kingdom
587
Rep
1,024
Posts

Drives: BMW M3 e92 08 & 330d e90 10
Join Date: Sep 2019
Location: UK, Surrey

iTrader: (0)

Garage List
2010 BMW 330d  [8.00]
2008 BMW M3  [0.00]
Stevenglan
Wow! Yea those on 3 & 4 were shot! Very lucky they didn't pick up!
Amazing mileage you got from those though! lol

Btw, unusual to see the lowers just as bad as the uppers, are they in their correct position?
__________________
Appreciate 1
DrFerry6725.50
      02-08-2024, 07:00 PM   #2977
Stevenglan
New Member
12
Rep
8
Posts

Drives: 2008 BMW M3 (E93)
Join Date: Feb 2024
Location: Cincinnati, OH

iTrader: (0)

For sure! And I was honestly surprised as well as I expected the top bearings to be in worse condition. I marked them with a paint pen on removal to ensure I kept the order.
Appreciate 2
DrFerry6725.50
      02-14-2024, 03:07 AM   #2978
uk215m3
New Member
18
Rep
19
Posts

Drives: e30 M3, e92 M3
Join Date: May 2022
Location: Qatar

iTrader: (0)

2012 e92 M3 - 96,000km Car was in dealer network under full warranty for 10 years so had OEM service schedule. Clean as a whistle. really dont see much wrong with these at all.








Last edited by uk215m3; 02-14-2024 at 03:21 AM..
Appreciate 2
DrFerry6725.50
      02-14-2024, 06:25 AM   #2979
DrFerry
Field Marshal
DrFerry's Avatar
United_States
6726
Rep
1,833
Posts

Drives: '08 E92 M3
Join Date: Jul 2010
Location: Greenville, SC

iTrader: (5)

Garage List
2008 BMW M3  [5.25]
2015 BMW X5  [4.50]
Quote:
Originally Posted by uk215m3 View Post
2012 e92 M3 - 96,000km Car was in dealer network under full warranty for 10 years so had OEM service schedule. Clean as a whistle. really dont see much wrong with these at all.







They do show some wear, but compared with many other examples in this thread they’re in relatively decent shape for an S65 engine at roughly 60K miles. What brand of bearings and bolts did you use to replace them with?
__________________
'08 E92 M3 DCT Melbourne Red/Bamboo Beige Leather/EDC/SSP Spec-R DCT clutch discs/SSP Pro-Gold DCT Fluid/Quaife LSD/3:45 Final Drive by Diffs Online/BE Bearings & ARP Bolts/Vibra Technics Engine Mounts/M3 World HFC X-Pipe/LUX H8 180/BPM Sport DCT Tune/PFC Z-Rated Pads/ECS Brass Brake Caliper Bushings/Alex Shop Solid Sub-frame Bushings/Motul 600/Tint
Appreciate 2
      02-14-2024, 12:34 PM   #2980
Assimilator1
Major
Assimilator1's Avatar
United Kingdom
587
Rep
1,024
Posts

Drives: BMW M3 e92 08 & 330d e90 10
Join Date: Sep 2019
Location: UK, Surrey

iTrader: (0)

Garage List
2010 BMW 330d  [8.00]
2008 BMW M3  [0.00]
Quote:
Originally Posted by uk215m3 View Post
2012 e92 M3 - 96,000km Car was in dealer network under full warranty for 10 years so had OEM service schedule. Clean as a whistle. really dont see much wrong with these at all.

........
Some mild surface wear and some flattening of the microgrooves it seems, yea not bad.
__________________
Appreciate 1
DrFerry6725.50
      02-19-2024, 08:47 PM   #2981
Al Bundy's Dodge
Captain
No_Country
1639
Rep
903
Posts

Drives: 2018 M2 6MT
Join Date: Jan 2018
Location: Denver

iTrader: (0)

2011 E92 47,000 miles

Looked good, definitely some wear, more so on uppers. First picture better represents how they all looked…2nd picture was dealing with shadows and I tried to brighten it up a bit.
Attached Images
  
__________________
2009 328i xDrive 6MT (Retired and I miss her)
2015 335i xDrive 6MT (Retired and I dont miss her)
2018 M2 6MT (Never retiring)

Last edited by Al Bundy's Dodge; 02-19-2024 at 09:03 PM..
Appreciate 2
DrFerry6725.50
      02-20-2024, 12:53 PM   #2982
Assimilator1
Major
Assimilator1's Avatar
United Kingdom
587
Rep
1,024
Posts

Drives: BMW M3 e92 08 & 330d e90 10
Join Date: Sep 2019
Location: UK, Surrey

iTrader: (0)

Garage List
2010 BMW 330d  [8.00]
2008 BMW M3  [0.00]
Quote:
Originally Posted by Al Bundy's Dodge View Post
2011 E92 47,000 miles

Looked good, definitely some wear, more so on uppers. First picture better represents how they all looked…2nd picture was dealing with shadows and I tried to brighten it up a bit.
Fancy carrying out a simple experiment on 1 or 2 of your old shells?
__________________
Appreciate 0
      02-21-2024, 08:56 PM   #2983
Al Bundy's Dodge
Captain
No_Country
1639
Rep
903
Posts

Drives: 2018 M2 6MT
Join Date: Jan 2018
Location: Denver

iTrader: (0)

Quote:
Originally Posted by Assimilator1 View Post
Fancy carrying out a simple experiment on 1 or 2 of your old shells?
PM me…have a lot going on over next month including some travel, so just depends what you are after, time available, etc…
__________________
2009 328i xDrive 6MT (Retired and I miss her)
2015 335i xDrive 6MT (Retired and I dont miss her)
2018 M2 6MT (Never retiring)
Appreciate 1
      02-29-2024, 09:24 AM   #2984
DrFerry
Field Marshal
DrFerry's Avatar
United_States
6726
Rep
1,833
Posts

Drives: '08 E92 M3
Join Date: Jul 2010
Location: Greenville, SC

iTrader: (5)

Garage List
2008 BMW M3  [5.25]
2015 BMW X5  [4.50]
MAHLE's S65/S85 replacement Rod Bearing research paper:
https://marmotorsport.com/wp-content...S85-Iss.-2.pdf
I can’t imagine buying S65 Rod bearings from a company that reached this conclusion regardless of the empirical evidence in the market place all over the world.
The rod bearing photo below is only an example given to illustrate the failure mode and taken from this thread:
https://www.m3post.com/forums/showpo...postcount=2615
.
Attached Images
  
__________________
'08 E92 M3 DCT Melbourne Red/Bamboo Beige Leather/EDC/SSP Spec-R DCT clutch discs/SSP Pro-Gold DCT Fluid/Quaife LSD/3:45 Final Drive by Diffs Online/BE Bearings & ARP Bolts/Vibra Technics Engine Mounts/M3 World HFC X-Pipe/LUX H8 180/BPM Sport DCT Tune/PFC Z-Rated Pads/ECS Brass Brake Caliper Bushings/Alex Shop Solid Sub-frame Bushings/Motul 600/Tint

Last edited by DrFerry; 03-02-2024 at 07:48 AM..
Appreciate 2
      03-01-2024, 01:26 PM   #2985
Product
Private First Class
No_Country
17
Rep
153
Posts

Drives: 2010 E90 M3
Join Date: Dec 2015
Location: Washington

iTrader: (2)

Work completed @ MPORIUM BMW, LLC
Fantastic folks over there.

2010 M3 sedan DCT
147,852k miles on original bearings.
Attached Images
 
Appreciate 2
DrFerry6725.50
      03-01-2024, 03:06 PM   #2986
PaulGros
Private
71
Rep
70
Posts

Drives: BMW E46
Join Date: Feb 2024
Location: UK

iTrader: (0)

Quote:
Originally Posted by DrFerry View Post
MAHLE's S65/S85 replacement Rod Bearing research paper:
https://marmotorsport.com/wp-content...S85-Iss.-2.pdf
I can’t imagine buying S65 Rod bearings from a company that reached this conclusion regardless of the empirical evidence in the market place all over the world.
.
OK, let's for a minute assume that MAHLE are incorrect. From the data I have seen (admittedly UK biased) actual engine failures are pretty rare. I'm open to be corrected on this. I'm not party to the origin of the bearings MAHLE have historically checked, it would be a reasonable assumption that they originated from BMW. The bearing picture in the report is from a set I submitted. These were used at my suggestion so any claims of selected samples to fit the conclusion could be disproven.

So what would be your theory / conclusion for the condition of the bearings we often see posted? Do you have data that I have possibly missed? Do you have any questions you would like me to pose to MAHLE on the subject? Company rules forbid them participating in forums / social media in any official capacity, but I can act as a go between.

My issue with the tight clearance theory is mainly centred on 4 points.

1. Early life failure would be normal with too little clearance, yet we are seeing bearings with 50,0000, 60,000, 70,000 + miles with no failure yet visually "worn" bearings.

2. Although the substrate is visible, it generally shows no signs of seizure or distress. The exception would be on engines that HAVE suffered catastrophic failure.

3. A number of these bearings have overlay no longer present / damaged in the counter bored area by the parting line. This is the part of the bearing with the largest clearance, so why the wear here? Excessive crush has been checked for and discounted as the steel backing had not distorted / yielded.

4. The actual drawing clearances have been made public and been shown to not be as tight as initially believed at 0.046mm nominal.


If you check back on posts, BE have conceded that this information is from a known and reputable source and should be trusted. I have personally met with Robert and so has the engineer who wrote the MAHLE report.

These are genuine questions, I have an unhealthy obsession with finding answers to problems. I spend a disproportionate amount of time on S65 bearings not because it generates a lot of turn over (it doesn't we have bearings that sell 100 times any volumes the S65 ever could) and bearing sales in total are around 10% of our business.

But, it is still a problem without a definitive answer so I keep digging. I genuinely don't believe there will be a eureka moment as I don't believe there is a single reason for all issues. But I do believe that collective minds sharing ideas and information openly have a far greater chance of piecing together the failure mode on these parts than any individual.

If all information is out in the public domain then that allows people to make an informed choice with full facts. If they then choose to not purchase MAHLE Motorsport then that is OK (for the S65 it's one of 3 brands we offer ) as long as that choice is made with full facts.
Appreciate 1
      03-01-2024, 09:00 PM   #2987
DrFerry
Field Marshal
DrFerry's Avatar
United_States
6726
Rep
1,833
Posts

Drives: '08 E92 M3
Join Date: Jul 2010
Location: Greenville, SC

iTrader: (5)

Garage List
2008 BMW M3  [5.25]
2015 BMW X5  [4.50]
Quote:
Originally Posted by PaulGros View Post
OK, let's for a minute assume that MAHLE are incorrect. From the data I have seen (admittedly UK biased) actual engine failures are pretty rare. I'm open to be corrected on this. I'm not party to the origin of the bearings MAHLE have historically checked, it would be a reasonable assumption that they originated from BMW. The bearing picture in the report is from a set I submitted. These were used at my suggestion so any claims of selected samples to fit the conclusion could be disproven.

So what would be your theory / conclusion for the condition of the bearings we often see posted? Do you have data that I have possibly missed? Do you have any questions you would like me to pose to MAHLE on the subject? Company rules forbid them participating in forums / social media in any official capacity, but I can act as a go between.

My issue with the tight clearance theory is mainly centred on 4 points.

1. Early life failure would be normal with too little clearance, yet we are seeing bearings with 50,0000, 60,000, 70,000 + miles with no failure yet visually "worn" bearings.

2. Although the substrate is visible, it generally shows no signs of seizure or distress. The exception would be on engines that HAVE suffered catastrophic failure.

3. A number of these bearings have overlay no longer present / damaged in the counter bored area by the parting line. This is the part of the bearing with the largest clearance, so why the wear here? Excessive crush has been checked for and discounted as the steel backing had not distorted / yielded.

4. The actual drawing clearances have been made public and been shown to not be as tight as initially believed at 0.046mm nominal.

If you check back on posts, BE have conceded that this information is from a known and reputable source and should be trusted. I have personally met with Robert and so has the engineer who wrote the MAHLE report.

These are genuine questions, I have an unhealthy obsession with finding answers to problems. I spend a disproportionate amount of time on S65 bearings not because it generates a lot of turn over (it doesn't we have bearings that sell 100 times any volumes the S65 ever could) and bearing sales in total are around 10% of our business.

But, it is still a problem without a definitive answer so I keep digging. I genuinely don't believe there will be a eureka moment as I don't believe there is a single reason for all issues. But I do believe that collective minds sharing ideas and information openly have a far greater chance of piecing together the failure mode on these parts than any individual.

If all information is out in the public domain then that allows people to make an informed choice with full facts. If they then choose to not purchase MAHLE Motorsport then that is OK (for the S65 it's one of 3 brands we offer ) as long as that choice is made with full facts.
Empirical evidence from the market place for blown engines is given in the "Blown Motors, Rod Bearing Failure" catalog thread linked below. It is a 123 page thread started in 2012. I joined the forum in 2010 and am familiar with it.

https://www.m3post.com/forums/showthread.php?t=786615

Scientific evidence for "Why do the motors blow with rod bearing failure" is given in the BE Bearings article linked below. Tolerance stacking, tight clearances and oil starvation due to thick oil are the main points of the study article.

https://www.bebearings.com/Overview.html

Early failures were seen and some are shown in the BE Bearings article linked above. There are too many failure mode factors to list, but here's a few that may have been overlooked: The advent of start/stop technology and its adoption by BMW around 2010 (I think) places more strain on engine components. The S65 has a 12:1 compression ratio. Reports of detonation are not uncommon. Some areas of the USA require different gasoline additives for smog reduction (CA for one) and lower octane (RON) gasoline blends which can exacerbate detonation. The S65 uses an ionic detonation detection system which employs the spark plugs and coil pack chip set to monitor detonation. The S65 uses a 10W60 multi-viscosity motor oil - in spite of tight rod bearing clearances and even in cold climates such as the northern states and Canada. The too 'thick oil' for tight clearances subject is discussed in the BE Bearings article linked above. The S65 crank journals appear to be too narrow to my eye. Admittedly this is speculation on my part, but even a BMC A-Series engine has wider crank journals (more surface area to spread the load).

You asked:
So what would be your theory / conclusion for the condition of the bearings we often see posted? Answer: OEM Bearing clearances that are too tight (especially in cases of tolerance stack up), and oil starvation at cold start up as well as high RPMs due to the OEM choice of 10W60 oil. This is the same oil viscosity spec used in the E46 S54 M3 which also suffered from rod bearing failures. My conclusion stems from the empirical market place observation that we do see rod bearing failures using the OEM bearings but we do not see bearing failures (yet that I know of) using increased clearance bearings - such as those which are - and have been for some time - available from B.E. Bearings.

Do you have data that I have possibly missed?
Answer: Yes, please study the information contained in the links I provided above.

Do you have any questions you would like me to pose to MAHLE on the subject?
Answer: Yes. Did MAHLE consider the empirical evidence from the market place showing hundreds of blown motors with OEM rod bearings and yet no blown engines with extra clearance bearings when coming to the conclusion the OEM bearing specs were "entirely satisfactory"?
__________________
'08 E92 M3 DCT Melbourne Red/Bamboo Beige Leather/EDC/SSP Spec-R DCT clutch discs/SSP Pro-Gold DCT Fluid/Quaife LSD/3:45 Final Drive by Diffs Online/BE Bearings & ARP Bolts/Vibra Technics Engine Mounts/M3 World HFC X-Pipe/LUX H8 180/BPM Sport DCT Tune/PFC Z-Rated Pads/ECS Brass Brake Caliper Bushings/Alex Shop Solid Sub-frame Bushings/Motul 600/Tint
Appreciate 2
      03-02-2024, 04:02 AM   #2988
Helmsman
Major General
Helmsman's Avatar
Sweden
4421
Rep
7,082
Posts

Drives: 2011 AW E90 M3 ZCP
Join Date: Mar 2014
Location: Stockholm, Sweden

iTrader: (0)

Quote:
Originally Posted by DrFerry View Post
Empirical evidence from the market place for blown engines is given in the "Blown Motors, Rod Bearing Failure" catalog thread linked below. It is a 123 page thread started in 2012. I joined the forum in 2010 and am familiar with it.
Would have been great with one thread Doc (3 posts?), much easier to follow and organise questions/answers in one (not the least for Paul who then only need one flame suit...) Interesting topic and surely lenghty, maybe use Pauls original thread instead of clutter a perfectly good general RB wear catalog?
Appreciate 2
      03-02-2024, 07:15 AM   #2989
DrFerry
Field Marshal
DrFerry's Avatar
United_States
6726
Rep
1,833
Posts

Drives: '08 E92 M3
Join Date: Jul 2010
Location: Greenville, SC

iTrader: (5)

Garage List
2008 BMW M3  [5.25]
2015 BMW X5  [4.50]
Quote:
Originally Posted by Helmsman View Post
Would have been great with one thread Doc (3 posts?), much easier to follow and organise questions/answers in one (not the least for Paul who then only need one flame suit...) Interesting topic and surely lenghty, maybe use Pauls original thread instead of clutter a perfectly good general RB wear catalog?
Paul addressed me specifically in this particular thread. Hence, only one reply by me here. My other post(s) (including this thread I thought I only made two) are in more obscure thread(s) and for information only. Those thread(s) are possibly less subscribed too. There is nothing about my post to Paul that would require a flame suit IMO. Hopefully you can understand my logic now.
__________________
'08 E92 M3 DCT Melbourne Red/Bamboo Beige Leather/EDC/SSP Spec-R DCT clutch discs/SSP Pro-Gold DCT Fluid/Quaife LSD/3:45 Final Drive by Diffs Online/BE Bearings & ARP Bolts/Vibra Technics Engine Mounts/M3 World HFC X-Pipe/LUX H8 180/BPM Sport DCT Tune/PFC Z-Rated Pads/ECS Brass Brake Caliper Bushings/Alex Shop Solid Sub-frame Bushings/Motul 600/Tint

Last edited by DrFerry; 03-02-2024 at 11:33 AM..
Appreciate 1
      03-02-2024, 10:23 AM   #2990
PaulGros
Private
71
Rep
70
Posts

Drives: BMW E46
Join Date: Feb 2024
Location: UK

iTrader: (0)

Quote:
Originally Posted by DrFerry View Post
Empirical evidence from the market place for blown engines is given in the "Blown Motors, Rod Bearing Failure" catalog thread linked below. It is a 123 page thread started in 2012. I joined the forum in 2010 and am familiar with it.

https://www.m3post.com/forums/showthread.php?t=786615

Scientific evidence for "Why do the motors blow with rod bearing failure" is given in the BE Bearings article linked below. Tolerance stacking, tight clearances and oil starvation due to thick oil are the main points of the study article.

https://www.bebearings.com/Overview.html

Early failures were seen and some are shown in the BE Bearings article linked above. There are too many failure mode factors to list, but here's a few that may have been overlooked: The advent of start/stop technology and its adoption by BMW around 2010 (I think) places more strain on engine components. The S65 has a 12:1 compression ratio. Reports of detonation are not uncommon. Some areas of the USA require different gasoline additives for smog reduction (CA for one) and lower octane (RON) gasoline blends which can exacerbate detonation. The S65 uses an ionic detonation detection system which employs the spark plugs and coil pack chip set to monitor detonation. The S65 uses a 10W60 multi-viscosity motor oil - in spite of tight rod bearing clearances and even in cold climates such as the northern states and Canada. The too 'thick oil' for tight clearances subject is discussed in the BE Bearings article linked above. The S65 crank journals appear to be too narrow to my eye. Admittedly this is speculation on my part, but even a BMC A-Series engine has wider crank journals (more surface area to spread the load).

You asked:
So what would be your theory / conclusion for the condition of the bearings we often see posted? Answer: OEM Bearing clearances that are too tight (especially in cases of tolerance stack up), and oil starvation at cold start up as well as high RPMs due to the OEM choice of 10W60 oil. This is the same oil viscosity spec used in the E46 S54 M3 which also suffered from rod bearing failures. My conclusion stems from the empirical market place observation that we do see rod bearing failures using the OEM bearings but we do not see bearing failures (yet that I know of) using increased clearance bearings - such as those which are - and have been for some time - available from B.E. Bearings.

Do you have data that I have possibly missed?
Answer: Yes, please study the information contained in the links I provided above.

Do you have any questions you would like me to pose to MAHLE on the subject?
Answer: Yes. Did MAHLE consider the empirical evidence from the market place showing hundreds of blown motors with OEM rod bearings and yet no blown engines with extra clearance bearings when coming to the conclusion the OEM bearing specs were "entirely satisfactory"?
I'm happy to put your points to MAHLE, my intention is to collate questions and submit them all at one time so please bear with me.

I will however, comment on some of your points.

1. OEM bearings theoretical clearance is 0.029 - 0.062mm with nominal 0.046mm – source OEM drawing.

2. They have commented on bearings seen (more than 1 set, see later post) as well as using the development data from their archives

3. I'm not familiar with US petrol (gas) but I would agree it is an interesting area that should be considered. Could the additional additives used in CA contribute to the bearing corrosion MAHLE reports? How can we prove / disprove this?

4. I'm not sure the A series would be a good comparison, The engine design is some 70 years old and was unique at the time due to the gearbox being located in the sump meaning the engine oil also lubricated the gear box. If you look at the Ford 1.6 EcoBoost engine (4 cylinder turbo, 200hp factory) we see a bearing width of 15.4mm with a 44.00mm shaft. Certainly in the UK in modified form these engines are regularly seen with 350hp +

5. I'm not convinced the oil viscosity is part of the issue. Now, I am far from an oil expert, but available technical papers suggest the opposite is true - the higher viscosity gives a thicker oil film. Example here https://www.substech.com/dokuwiki/do...il%20viscosity
Appreciate 0
      03-03-2024, 10:31 PM   #2991
Scharbag
Colonel
Scharbag's Avatar
Canada
2619
Rep
2,138
Posts

Drives: 2011 E92 M3
Join Date: Oct 2017
Location: Victoria

iTrader: (0)

Garage List
2011 BMW E92 M3  [0.00]
Quote:
Originally Posted by PaulGros View Post
I'm happy to put your points to MAHLE, my intention is to collate questions and submit them all at one time so please bear with me.

I will however, comment on some of your points.

1. OEM bearings theoretical clearance is 0.029 - 0.062mm with nominal 0.046mm – source OEM drawing.

2. They have commented on bearings seen (more than 1 set, see later post) as well as using the development data from their archives

3. I'm not familiar with US petrol (gas) but I would agree it is an interesting area that should be considered. Could the additional additives used in CA contribute to the bearing corrosion MAHLE reports? How can we prove / disprove this?

4. I'm not sure the A series would be a good comparison, The engine design is some 70 years old and was unique at the time due to the gearbox being located in the sump meaning the engine oil also lubricated the gear box. If you look at the Ford 1.6 EcoBoost engine (4 cylinder turbo, 200hp factory) we see a bearing width of 15.4mm with a 44.00mm shaft. Certainly in the UK in modified form these engines are regularly seen with 350hp +

5. I'm not convinced the oil viscosity is part of the issue. Now, I am far from an oil expert, but available technical papers suggest the opposite is true - the higher viscosity gives a thicker oil film. Example here https://www.substech.com/dokuwiki/do...il%20viscosity
This goes round and round.

BMW nominal clearance is less than recommended by EVERY DAMN PROFESSIONAL ENGINE BUILDER ON EARTH!

The failure mode is diagnostic of flow starvation based on available literature (low flow due to tight bearings).

Not one single engine has blown up with properly sized bearings to date (due to rod bearing failure alone).

Many properly sized bearings have been pulled showing pristine shells after many hard miles (search, you can find them).

There is so much good hard data available - I am disappointed that this is still being “debated.”
__________________

2011 E92 M3 - 6MT, ZCP, ZF LSD, ESS G1, Some other goodies...
Appreciate 1
jvictormp881.00
      03-04-2024, 02:54 AM   #2992
Sneaky Pete
Second Lieutenant
83
Rep
284
Posts

Drives: M car
Join Date: Jan 2016
Location: Wild blue yonder

iTrader: (0)

Quote:
Originally Posted by Scharbag View Post
This goes round and round.

BMW nominal clearance is less than recommended by EVERY DAMN PROFESSIONAL ENGINE BUILDER ON EARTH!
You are a bit behind the curve there buddy.
Part of the original Glacier Vandervell drawing has been recently released showing the OEM bearings nominal clearance at 0.046mm.
A clearance in line with previous generations of M cars and the Clevite white paper.
Anything you ever read about S65 tight bearing clearance can be disregarded.
Appreciate 2
Post Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -5. The time now is 05:50 PM.




m3post
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST