THE M3 IS GETTING THE ANRI BUILD TREATMENT - Blown headgasket to build thread

[ChapterM3]

Anri - Man. I have to digest what I’m reading about the rod bearings and these ARP bolts. I did those thinking this was an upgrade that would help PROLONG the rod bearing service. So essentially this is a ton of premature wear that’s gone on because of the lack of resizing of the rods? These will obviously then need to be replaced considering they’re already out of the car. I didn’t even know that would be a thing that would need to be done, as you said ARP hides that detail and is a mere suggestion than it is as mandatory. F man that’s a hard pill to swallow. On another note - The cylinders are looking incredible with the new moly coating, thank you for all these photos. Looking forward to more updates!

[bimmerfan08]

Lol forgetting one word completely changed that post. The engineer said it was NOT necessary.

But its still a good practice that I follow.

That definitely changed the advice in the post. 😅

[George Hill]

This was my take. When I replaced the rod bearings in my S54, I carefully noted and marked each M11 bolt and its matching hole. I documented this on page 188 in my DIY below.

https://drive.google.com/file/d/1pLmaagppKMehpCgdw32cjcaZ0iCMuZDo/view

Lol forgetting one word completely changed that post. The engineer said it was NOT necessary.

But its still a good practice that I follow.

[bimmerfan08]

Just an FYI, BMW published information saying the early M11 bolts were hole specific in regards to the connecting rod location. When I was at the dealer back in 2012 or so I was chatting with an engineer about this and he said that it was necessary and BMW published that in hopes that it would lead to potentially less technician at fault failures during the RB recall.

This was my take. When I replaced the rod bearings in my S54, I carefully noted and marked each M11 bolt and its matching hole. I documented this on page 188 in my DIY below.

https://drive.google.com/file/d/1pLmaagppKMehpCgdw32cjcaZ0iCMuZDo/view

[George Hill]

My understanding is that early connecting rods (with the M11 bolt variant) were matched individually to connecting rod bolts.

Just an FYI, BMW published information saying the early M11 bolts were hole specific in regards to the connecting rod location. When I was at the dealer back in 2012 or so I was chatting with an engineer about this and he said that it was NOT necessary and BMW published that in hopes that it would lead to potentially less technician at fault failures during the RB recall.

[Anri]

kaiv might be able to give some insight on the early rod and APR M11 combo using the stretch method. By now, he could have done a third or fourth bearing replacement on a track car and reused the APR M11s.

Lang in SoCal was the only one who posted the early rod bore measurements using that combo and that got lost with the old forum.

Slideways,

Nothing new under the sun. It's standard measurement
during engine building. I did it with this current set up as
well and found interesting data..

I believe you are missing major point here.

[Slideways]

Hi, Anri. Would like to explore this comment a bit further.

My understanding is that early connecting rods (with the M11 bolt variant) were matched individually to connecting rod bolts. The later bolts (M10 variant) are not rod-exclusive given their TTY design, IIRC. Does your comment only apply to rods with M11 bolts or is it across the board for all S54 connecting rods?

kaiv might be able to give some insight on the early rod and APR M11 combo using the stretch method. By now, he could have done a third or fourth bearing replacement on a track car and reused the APR M11s.

Lang in SoCal was the only one who posted the early rod bore measurements using that combo and that got lost with the old forum.

[Anri]

Hi, Anri. Would like to explore this comment a bit further.

My understanding is that early connecting rods (with the M11 bolt variant) were matched individually to connecting rod bolts. The later bolts (M10 variant) are not rod-exclusive given their TTY design, IIRC. Does your comment only apply to rods with M11 bolts or is it across the board for all S54 connecting rods?

Hi,

I have single point. M9 M10 M11 M12 M13 list goes
if the rod is machined with specific Rod bolt keep it
with that rod bolt design new or re-use the old one.

If the rods are out on the table then it does not matter
which one you chose because they will be re-sized given
your bolts choice.

Regards,
Anri

[Anri]

can you post a picture of all the removed rod bearings?

Earlier today I was able to pull few from the trash and
they all looked the same. Note the dark side is all even
which I not good and the next stage is like the worst one.

Remember these bearings have only 20k miles on them.

[bimmerfan08]

Sapote,

When the factory rods were made they were machined with the
factory specific bolts and specific clash is achieved with this bolt
design.

When one replaces the bolts with other than intended one
then the side Clash changes and it tights up the oil clearance
because the 2mm bearing shell takes the shape of the BE

It also matters how you torque the bolts...

Again, ARP at row # 7 politely saying "should be re-seized"

Can you imagine if you bring me your M3 and ask me Anri can you
replace my rod bolts with ARP and I answer you back it will cost
you $15k because I have to take the engine apart....

Clear?

Regards,
Anri

Hi, Anri. Would like to explore this comment a bit further.

My understanding is that early connecting rods (with the M11 bolt variant) were matched individually to connecting rod bolts. The later bolts (M10 variant) are not rod-exclusive given their TTY design, IIRC. Does your comment only apply to rods with M11 bolts or is it across the board for all S54 connecting rods?

[ZiMMie]

Moving to the rod, bearings, bolts.

In S54 industry is a Fashion to use ARP rod bolts rather than looking at how it works.

ARP Manufactures great products.

Any of those who install ARP are aware of that if one is using different bolt
design the connecting rod Must be re-sized ? In the Instructional sheet row Special
ARP politely says "Should always be re-sized", its worded very clever and R@R
options do love to load up the bill with parts and the Motor "it better than factory"
is the go.

Jonathan you paid money to have your freshly 20k miles bearing/s shown in the pic
look like they are 150k miles and you are not even tracking this car...if it was tracked...
then for sure the rod knock...

The evidence shows the bolt were placed without using ARP hi torque moly grease
it is also important how the bolts is torqued.

In the picture bellow pay attention on the rod side, the bearing has darker spots means
increased tension.

Moving forward.

Regards,
Anri

can you post a picture of all the removed rod bearings?

[Anri]

Pistons skirts are all dressed in Moly so do
the ACL bearings.

Moving forward.

[Anri]

Anri,
So the ARP bolts have less stress lengthwise under the same torque spec, and this caused the bearing clearance to be less than spec?

Sapote,

When the factory rods were made they were machined with the
factory specific bolts and specific clash is achieved with this bolt
design.

When one replaces the bolts with other than intended one
then the side Clash changes and it tights up the oil clearance
because the 2mm bearing shell takes the shape of the BE

It also matters how you torque the bolts...

Again, ARP at row # 7 politely saying "should be re-seized"

Can you imagine if you bring me your M3 and ask me Anri can you
replace my rod bolts with ARP and I answer you back it will cost
you $15k because I have to take the engine apart....

Clear?

Regards,
Anri

[sapote]

Anri,
So the ARP bolts have less stretch lengthwise under the same torque spec, and this caused the bearing clearance to be less than spec?

[Anri]

Moving to the rod, bearings, bolts.

In S54 industry is a Fashion to use ARP rod bolts rather than looking at how it works.

ARP Manufactures great products.

Any of those who install ARP are aware of that if one is using different bolt
design the connecting rod Must be re-sized ? In the Instructional sheet row # 7
ARP politely says "Should always be re-sized", its worded very clever and R@R
options do love to load up the bill with parts and the Motor "it better than factory"
is the go.

Jonathan you paid money to have your freshly 20k miles bearing/s shown in the pic
look like they are 150k miles and you are not even tracking this car...if it was tracked...
then for sure the rod knock...

The evidence shows the bolt were placed without using ARP hi torque moly grease
it is also important how the bolts is torqued.

In the picture bellow pay attention on the rod side, the bearing has darker spots means
increased tension.

Moving forward.

Regards,
Anri