[bradleyland]

Originally Posted by RPM2-85

And this again means what!?!? What if the block is unique to the M2? No absolute proof of that not being truth either. Fact remains, BMW advertises it to this day as closed. Until it is proven with photos, of a disassembled engine, thats the best information anyone can rely on. Period....

Obviously there are a lot of you non M2 owners who care deeply if this engine is closed. This mystery wont last forever....

Ill be happy to know the truth.

It means that both the X4 M40i and M2, which both use the N55B30T0 use an engine block that is not available as a separate part.

I'm not sure if you saw zenmaster's post, but I'll extract the important bit:

The N55 in the BMW M2 and BMW X4 M40i xDrive are indeed closed deck. The head gasket is the same as it didn’t require any adaptations even if it is now a closed deck design.

I simply find it interesting that the block portion of the N55B30T0 isn't available as a separate part. I never said it was definitive, I said it corroborated what zenmaster had posted, and that it refined my thinking about the situation.

You seem a little agitated, based on the "!?!?" — maybe just emphatic — but in the absence of actual observation, it's just kind of fun (for me anyway) to dig through the details and see if we can filter out any clues.

[bradleyland]

Originally Posted by zenmaster

I'm also curious why the M2 uses a different turbo part no. What are the actual differences? It's supposed to be the same size as that used in the M235i, and is integrated into the exhaust manifold in the same manner.

Part number changes aren't all that uncommon, even for parts that don't change specification. Any little change can trigger a revision.

I too, am curious exactly what the difference is, but we already know what counts: that the turbocharger on the M2 is near its limit. We know this from the tuning that has already happened.

[reppucci]

Originally Posted by bradleyland

Part number changes aren't all that uncommon, even for parts that don't change specification. Any little change can trigger a revision.

I too, am curious exactly what the difference is, but we already know what counts: that the turbocharger on the M2 is near its limit. We know this from the tuning that has already happened.

turbo for m2 is unique and bigger; i.e. different than the M235i turbo but also integrated into exhaust manifold. X4M40i has the m235 turbo but M2 block. That accounts for the horsepower difference of 15 between M2 and M40i.

The m2 and x4 m40i engines N55B30T0 are otherwise identical!

[reppucci]

Originally Posted by RPM2-85

And this again means what!?!? What if the block is unique to the M2? No absolute proof of that not being truth either. Fact remains, BMW advertises it to this day as closed. Until it is proven with photos, of a disassembled engine, thats the best information anyone can rely on. Period....

Obviously there are a lot of you non M2 owners who care deeply if this engine is closed. This mystery wont last forever....

Ill be happy to know the truth.

x40i and M2 blocks are identical. Same engine; N55B30T0. The turbos and maybe software are different. Internals are identical.

Based on realOEM it seems that there is a block difference between the N55B30T0 and N55B30O0. Unless the block part number includes the pistons? (that is how the block part number is listed for the M235. Block and pistons, look it up on my prior post) That is different for the M2 and M40i block since they use s55 pistons and unique rings.

Lots of questions re open vs closed deck... I don't know I am ready to commit one way or another. However I do agree it doesn't mean diddly squat. The M2 motor is awesome.

As i have previously said.. Time will tell!

[M3 Adjuster]

Originally Posted by reppucci

turbo for m2 is unique and bigger; i.e. different than the M235i turbo but also integrated into exhaust manifold. X4M40i has the m235 turbo but M2 block. That accounts for the horsepower difference of 15 between M2 and M40i.

The m2 and x4 m40i engines N55B30T0 are otherwise identical!

True story. I thought this was common knowledge though.

[reppucci]

Originally Posted by M3 Adjuster

True story. I thought this was common knowledge though.

Me too!

[oldmanstyle]

Originally Posted by bradleyland

Sorry to be pedantic, but there is no N55TU.

Pardon the shorthand but trying to keep it simple. The N55 in the M2 is a technical update so it works for the purpose of this discussion.

Originally Posted by bradleyland

On the converse, there's no real reason to do a closed-deck design at these power levels.

And there is a real reason for using the forged S55 rotating assembly at 365 hp?

Originally Posted by bradleyland

The forged crank and other special bits are ball parts bin grabs. They're components that are used elsewhere. A change to closed deck would mean:

They are parts bin but there is still a cost to them. If they're not needed at 365 hp, why spend the money?

[RPM2-85]

Originally Posted by bradleyland

It means that both the X4 M40i and M2, which both use the N55B30T0 use an engine block that is not available as a separate part.

I'm not sure if you saw zenmaster's post, but I'll extract the important bit:



I simply find it interesting that the block portion of the N55B30T0 isn't available as a separate part. I never said it was definitive, I said it corroborated what zenmaster had posted, and that it refined my thinking about the situation.

You seem a little agitated, based on the "!?!?" — maybe just emphatic — but in the absence of actual observation, it's just kind of fun (for me anyway) to dig through the details and see if we can filter out any clues.

The thread went so fast on me I missed a page. My bad. Well the engine is a closed deck block in my mind. Ive seen everything I need to see.

[oldmanstyle]

Originally Posted by Artemis

The R&D cost of redesiging an engine is one thing.

The production cost to manufacture the redesigned engine is another thing.

Budgets got to be respected if a car manufacturer wants to keep the price of the car competitive and 'respect' the hierarchy of the portfolio.

We don't know the numbers though. You're presupposing it's open deck based on the fact that it would cost X more to manufacture a closed deck block. The reality is none of us know what X BMW is comfortable with, or if it's peanuts in the grand scheme of M2 development.

Originally Posted by Artemis

If the N55B30T0 engine (M2) got a 'closed deck' design, then why didn't BMW optimize that engine further with LDS-coated aluminium cylinder liners ?

R&D and manufacturing budget

[Artemis]

Originally Posted by reppucci

x40i and M2 blocks are identical. Same engine; N55B30T0. The turbos and maybe software are different. Internals are identical.

Well, then let's also have also a closer look at the X4 M40i press releases too.

X4 M40i US press release of October 1, 2015 (available here - full PDF document here): alike the M2 US press release of October 14, 2015 (available here - full PDF document here) reference is made to a 'closed deck' design:

"The newly developed M Performance TwinPower Turbo inline 6 cylinder gasoline engine for the new BMW X4 M40i combines high performance with exemplary fuel economy. Accordingly, the lightweight, thermodynamically optimized aluminium engine has been constructed with a closed-deck design. In this type of construction, the water jacket surrounding the cylinders is sealed at the top, which endows the crankcase with an exceptionally high degree of stiffness."

X4 M40i German press release of February 17, 2016 (available here - full PDF document here): alike the updated M2 German press release of February 17, 2016 (same day) the reference to 'closed deck' design has vanished (available here - updated full PDF document here):

"Der neue BMW X4 M40i verfügt über einen neu entwickelten M Performance TwinPower Turbo Reihen-Sechszylinder-Benzinmotor. Das leichte, thermodynamisch optimierte Aluminium-Triebwerk wurde auf maximale Drehfreude bei gleichzeitig souveränem Durchzugsvermögen ausgelegt und bietet dementsprechend eine Motorcharakteristik, die begeisternde Fahrdynamik mit beeindruckender Effizienz verbindet."

So zenmaster, does your source have a sound explanation for the update by BMW AG in February 2016 of the October 2015 German press releases for both the M2 and X4 M40i with no 'closed deck' design references anymore ?

[zenmaster]

Originally Posted by Artemis

So zenmaster, does your source have a sound explanation for the update by BMW AG in February 2016 of the October 2015 German press releases for both the M2 and X4 M40i with no 'closed deck' design references anymore ?

Issue is closed for me. Non interesting and a circle jerk.

[RPM2-85]

Originally Posted by Artemis

Well, then let's also have also a closer look at the X4 M40i press releases too.

X4 M40i US press release of October 1, 2015 (available here - full PDF document here): alike the M2 US press release of October 14, 2015 (available here - full PDF document here) reference is made to a 'closed deck' design:

"The newly developed M Performance TwinPower Turbo inline 6 cylinder gasoline engine for the new BMW X4 M40i combines high performance with exemplary fuel economy. Accordingly, the lightweight, thermodynamically optimized aluminium engine has been constructed with a closed-deck design. In this type of construction, the water jacket surrounding the cylinders is sealed at the top, which endows the crankcase with an exceptionally high degree of stiffness."

X4 M40i German press release of February 17, 2016 (available here - full PDF document here): alike the updated M2 German press release of February 17, 2016 (same day) the reference to 'closed deck' design has vanished (available here - updated full PDF document here):

"Der neue BMW X4 M40i verfügt über einen neu entwickelten M Performance TwinPower Turbo Reihen-Sechszylinder-Benzinmotor. Das leichte, thermodynamisch optimierte Aluminium-Triebwerk wurde auf maximale Drehfreude bei gleichzeitig souveränem Durchzugsvermögen ausgelegt und bietet dementsprechend eine Motorcharakteristik, die begeisternde Fahrdynamik mit beeindruckender Effizienz verbindet."

So zenmaster, does your source have a sound explanation for the update by BMW AG in February 2016 of the October 2015 German press releases for both the M2 and X4 M40i with no 'closed deck' design references anymore ?

Dude drop it already........ They probably dropped it to push closed deck on the B58 as a special feature.

This issue is "closed". Be happy your car has some special engine features compared to the rest of the N55 batches. A really a great motor has been put in this car.

[SoCalRob]

Originally Posted by Artemis

So zenmaster, does your source have a sound explanation for the update by BMW AG in February 2016 of the October 2015 German press releases for both the M2 and X4 M40i with no 'closed deck' design references anymore ?

Does anyone know whether the BMW AG press releases for the M3/M4 (F80/F82) specifically called out 'closed deck' designs?

In other words, is it typical or atypical to include this level of detail in press releases?

I tried sifting through old press releases on their website, but, given my woeful German language skills, I eventually just gave up. -scr

[Artemis]

Originally Posted by zenmaster

Issue is closed for me. Non interesting and a circle jerk.

Engine pictures will silence the discussion. Someday these will pop up over here.

[Artemis]

Originally Posted by SoCalRob

Does anyone know whether the BMW AG press releases for the M3/M4 (F80/F82) specifically called out 'closed deck' designs?
In other words, is it typical or atypical to include this level of detail in press releases?
I tried sifting through old press releases on their website, but, given my woeful lack of German language skills, I eventually just gave up. -scr

It's an indisputable fact that the S55B30T0 engine (M3/M4) features a 'closed deck' design.

FWIW, BMW AG indeed referred to it in its M3/M4 German press release of May 9, 2014 (available here - full PDF document here):

"Das Kurbelgehäuse des Sechszylinder-Motors ist dank seiner sogenannten Closed-Deck-Bauweise besonders steif und ermöglicht somit höhere Zylinderdrücke und damit eine bessere Leistungsausbeute. Seine buchsenlosen, LDS-beschichteten Zylinderlaufbahnen tragen maßgeblich zu einer deutlichen Gewichtsreduzierung bei."

The same paragraph features in the BMW Global English M3/M4 press release of May 9, 2014 (available here - full PDF document here):

"The six-cylinder engine features a closed-deck crankcase design which is very rigid and allows cylinder pressures to be increased for improved power output. And instead of liners, the cylinder bores feature a twin-wire arc-sprayed coating, which results in a significant reduction in engine weight."

[ric124]

Originally Posted by Artemis

Engine pictures will silence the discussion. Someday these will pop up over here.

Agreed! Who is will to pull the head off their M2 and take pic?

[reppucci]

Originally Posted by Artemis

Engine pictures will silence the discussion. Someday these will pop up over here.

patience and time will reveal the truth

[bradleyland]

Originally Posted by Artemis

It's an indisputable fact that the S55B30T0 engine (M3/M4) features a 'closed deck' design.

FWIW, BMW AG indeed referred to it in its M3/M4 German press release of May 9, 2014 (available here - full PDF document here):

"Das Kurbelgehäuse des Sechszylinder-Motors ist dank seiner sogenannten Closed-Deck-Bauweise besonders steif und ermöglicht somit höhere Zylinderdrücke und damit eine bessere Leistungsausbeute. Seine buchsenlosen, LDS-beschichteten Zylinderlaufbahnen tragen maßgeblich zu einer deutlichen Gewichtsreduzierung bei."

The same paragraph features in the BMW Global English M3/M4 press release of May 9, 2014 (available here - full PDF document here):

"The six-cylinder engine features a closed-deck crankcase design which is very rigid and allows cylinder pressures to be increased for improved power output. And instead of liners, the cylinder bores feature a twin-wire arc-sprayed coating, which results in a significant reduction in engine weight."

I don't think SoCalRob was disputing the fact that the S55 is closed deck. His inquiry is in the interest of uncovering consistency/inconsistency between the German-market and non-German-market press materials. That's my understanding based on this quote:

Originally Posted by SoCalRob

Does anyone know whether the BMW AG press releases for the M3/M4 (F80/F82) specifically called out 'closed deck' designs?

In other words, is it typical or atypical to include this level of detail in press releases?

I tried sifting through old press releases on their website, but, given my woeful German language skills, I eventually just gave up. -scr

So your findings confirm that BMW consistently marketed the closed-deck aspect of the S55 in all German and global press releases. This is inconsistent with the way they have marketed the N55B30T0.

What we have here is a mountain of inconsistency lol.

[SoCalRob]

Originally Posted by bradleyland

What we have here is a mountain of inconsistency lol.

Indeed. However, at this point, it's fair to note that we have at least a couple of ostensibly knowledgeable BMW technical insiders unambiguously confirming 'closed deck'.

By contrast, the only info we have against 'closed deck' is the absence of those words in some BMW press releases, not concrete statements to the contrary.

Official BMW press releases from numerous other countries still claim 'closed deck', such as the BMW UK press release, dated April 11, 2016.

Regards. -scr

[Artemis]

Originally Posted by bradleyland

I don't think SoCalRob was disputing the fact that the S55 is closed deck. His inquiry is in the interest of uncovering consistency/inconsistency between the German-market and non-German-market press materials. That's my understanding based on this quote

It was no reference to forum fellow SoCalRob. I merely added that S55 fact for the reasoning developed in that post.

Originally Posted by SoCalRob

Indeed. However, at this point, it's fair to note that we have at least a couple of ostensibly knowledgeable BMW technical insiders unambiguously confirming 'closed deck'.
By contrast, the only info we have against 'closed deck' is the absence of those words in some BMW press releases, not concrete statements to the contrary.
Official BMW press releases from numerous other countries still claim 'closed deck', such as the BMW UK press release, dated April 11, 2016.

I concur.

I am by no means affiliated to BMW (except from being a loyal customer), so got no authority to make any claims whatsoever. But that does not imply that I may not point out - FWIW - a discrepancy between some original and updated M2 and X4 M40i press materials.

As told earlier: the truth is out there, more particularly under the hood.

[SeanWRT]

Gentlemen, this thread should be closed as we're pretty sure turbo is the same. The discussion on open/close deck is a bit off topic but certainly deserves a new dedicated thread.

[FSociety]

When BD_F87 brings his M2 to our local tuner to baseline on Dynojet & then see its potential with the flash and custom parameters.