Are BMW actually a joke how smart they are?

[Slow]

Was watching a guy working on his E60 M5 doing rod bearings etc.He gets to removing the rods and caps.

Then the talk of fracture split connecting rods where they make the rod and cap as a single piece then snap them to get each half.

They look like this.



Go to 21 minute onwards to see what I am talking about.

https://www.youtube.com/watch?v=LMDTXlgZeV4

Is this BMW being secretly full blown genius or pointless? I have never seen something like this in my life, admittedly I dont rip apart that many engines.

[Triumph Man]

There's quite a few engines like that. As a Land Rover/Range Rover man, you may be interested to know that I believe the Lion V6 and V8 also have fracture split rods (from what I've read anyway - somebody may correct me!)

[CraigyMc]

Slow said:

Was watching a guy working on his E60 M5 doing rod bearings etc.He gets to removing the rods and caps.

Then the talk of fracture split connecting rods where they make the rod and cap as a single piece then snap them to get each half.

They look like this.



Go to 21 minute onwards to see what I am talking about.

https://www.youtube.com/watch?v=LMDTXlgZeV4

Is this BMW being secretly full blown genius or pointless? I have never seen something like this in my life, admittedly I dont rip apart that many engines.

Fracture splitting conrods during manufacturing like that isn't a BMW secret sauce thing. It's a totally normal manufacturing process used by loads of manufacturers. It allows a forged rod to be made in one piece, fractured, installed, and then once installed it's back to original shape with all the crystalline paths through the structure set up correctly as they were when it was forged.

[TheLurker]

CraigyMc said:

Fracture splitting conrods during manufacturing like that isn't a BMW secret sauce thing. It's a totally normal manufacturing process used by loads of manufacturers. It allows a forged rod to be made in one piece, fractured, installed, and then once installed it's back to original shape with all the crystalline paths through the structure set up correctly as they were when it was forged.

So it's actually a good thing rather than a cost saving measure?

[CraigyMc]

TheLurker said:

CraigyMc said:

Fracture splitting conrods during manufacturing like that isn't a BMW secret sauce thing. It's a totally normal manufacturing process used by loads of manufacturers. It allows a forged rod to be made in one piece, fractured, installed, and then once installed it's back to original shape with all the crystalline paths through the structure set up correctly as they were when it was forged.

So it's actually a good thing rather than a cost saving measure?

Bit of both really.

[CraigyMc]

Further reading for anyone interested - https://patents.google.com/patent/US6961997B2/en (recent, well written patent on the modern way this is done).

and 1948 patent which is the earliest I can find, referring to a fracture-manufactured conrod; https://patents.google.com/patent/US2553935A/en

Edited by CraigyMc on Thursday 9th March 12:13

[vw_99]

https://www.pistonheads.com/gassing/topic.asp?h=0&...

[Chris32345]

Slow said:

Was watching a guy working on his E60 M5 doing rod bearings etc.He gets to removing the rods and caps.

Then the talk of fracture split connecting rods where they make the rod and cap as a single piece then snap them to get each half.

They look like this.



Go to 21 minute onwards to see what I am talking about.

https://www.youtube.com/watch?v=LMDTXlgZeV4

Is this BMW being secretly full blown genius or pointless? I have never seen something like this in my life, admittedly I dont rip apart that many engines.

you a few are like that now get closer for apperntly,

[SturdyHSV]

The Americans do it too, LS rods are the same from GM for example.

[stevieturbo]

Slow said:

Was watching a guy working on his E60 M5 doing rod bearings etc.He gets to removing the rods and caps.

Then the talk of fracture split connecting rods where they make the rod and cap as a single piece then snap them to get each half.

They look like this.



Go to 21 minute onwards to see what I am talking about.

https://www.youtube.com/watch?v=LMDTXlgZeV4

Is this BMW being secretly full blown genius or pointless? I have never seen something like this in my life, admittedly I dont rip apart that many engines.

cracked caps have been quite common for 2-3 decades.

[stevieturbo]

Now this is "smart"....some amazing machining

Ascaso engineering on their rod for their fancy A-series based engine

https://www.facebook.com/111874667308270/photos/pb...

[LunarOne]

No, but it's a joke how good Sreten of M539 Restorations is at fixing BMWs and making engaging Youtube content. A new video from him literally brightens my day. And each and every video gets better. Probably one of my top 3 Youtube channels of all time. He even gets Alpina sending him bits for free as they are fans of what he does too.

[MikeM6]

LunarOne said:

No, but it's a joke how good Sreten of M539 Restorations is at fixing BMWs and making engaging Youtube content. A new video from him literally brightens my day. And each and every video gets better. Probably one of my top 3 Youtube channels of all time. He even gets Alpina sending him bits for free as they are fans of what he does too.

Absolutely, I genuinely love watching his videos, he has such a brilliant approach.

He also makes me feel wholly hopelessly useless at spannering at the same time as inspiring me to think I could have a go haha!

[Megaflow]

stevieturbo said:

Slow said:

Was watching a guy working on his E60 M5 doing rod bearings etc.He gets to removing the rods and caps.

Then the talk of fracture split connecting rods where they make the rod and cap as a single piece then snap them to get each half.

They look like this.



Go to 21 minute onwards to see what I am talking about.

https://www.youtube.com/watch?v=LMDTXlgZeV4

Is this BMW being secretly full blown genius or pointless? I have never seen something like this in my life, admittedly I dont rip apart that many engines.

cracked caps have been quite common for 2-3 decades.

Yup. There a few blocks out there now with fracture split main caps as well.

[Triumph Man]

MikeM6 said:

LunarOne said:

No, but it's a joke how good Sreten of M539 Restorations is at fixing BMWs and making engaging Youtube content. A new video from him literally brightens my day. And each and every video gets better. Probably one of my top 3 Youtube channels of all time. He even gets Alpina sending him bits for free as they are fans of what he does too.

Absolutely, I genuinely love watching his videos, he has such a brilliant approach.

He also makes me feel wholly hopelessly useless at spannering at the same time as inspiring me to think I could have a go haha!

To echo you both, I feel the same way! The stuff he does is incredible. I really felt for him when the rebuilt Alpina engine broke on the test drive

[HJG]

Almost every engine on the road has fracture split con rods.

[bolide]

I would think the main advantage is that you can machine a perfectly round hole for the bearings, rather than machining two half-round parts

[stevieturbo]

bolide said:

I would think the main advantage is that you can machine a perfectly round hole for the bearings, rather than machining two half-round parts

What ?


Rods are machined round assembled, the bearing hole is not machined as two halves.

[DVandrews]

The idea is to do away with cap walk, location of the cap to the rod is perfect and requires no dowelling, also the grain flow of the forging around the big end eye is perfect.

Dave

[stevieturbo]

one version of the cracking.

https://www.youtube.com/watch?v=QlVrDJBiqd4