[raysspl]

Never really a fan of any of the motoman reviews...

[N54B30A]

Originally Posted by ROBNYC

+1

Do they mention anything about the actual crank or rods being shared with the s55?

[FSociety]

Originally Posted by sahyoun

Do they mention anything about the actual crank or rods being shared with the s55?

Forged steel crankshaft
Pistons with a modified top ring

But I'm pretty sure there's a mention in the technical doc of a rod somewhere don't remember

[sth519]

http://f87.bimmerpost.com/forums/sho....php?t=1224109

More details than any review will be able to cover.

[N54B30A]

Originally Posted by ROBNYC

Forged steel crankshaft
Pistons with a modified top ring

But I'm pretty sure there's a mention in the technical doc of a rod somewhere don't remember

Yeah, the word rod wasn't even mentioned so who knows. In terms of having a car to keep and mod, the m2 just seems like a deal of a lifetime. You can always upgrade the cooling and turbos to be equal to or better than the m4. Not to mention it has a hell of a lot more block rigidity considering its got massive iron sleeves. I wonder what the differences in the head are.

[zenmaster]

Originally Posted by sahyoun

Do they mention anything about the actual crank or rods being shared with the s55?

Same rods and crank as 235. Apparently same pistons also but with different rings.
The S55's lighter magnesium alloy crank was not used.

[BruceM]

Originally Posted by sahyoun

Yeah, the word rod wasn't even mentioned so who knows. In terms of having a car to keep and mod, the m2 just seems like a deal of a lifetime. You can always upgrade the cooling and turbos to be equal to or better than the m4. Not to mention it has a hell of a lot more block rigidity considering its got massive iron sleeves. I wonder what the differences in the head are.

That is certainly my hope. That way, you make the M2 a better 1M, not a better M4....

[N54B30A]

Originally Posted by zenmaster

Same rods and crank as 235. Apparently same pistons also but with different rings.
The S55's lighter magnesium alloy crank was not used.

That would make sense if the m4 used a magnesium alloy crank. The crank in the m4 is a steel alloy, theres absolutely no magnesium in it. You may be thinking of the oil pan. The M4's crank uses 42CrMoS4 steel alloy found here: http://www.steelnumber.com/en/steel_...hp?name_id=195

Magnesium is not even close to an ideal alloy for load bearing engine internals. Where did you hear that its using the m235i's crank? Theres no information I could find on that...

They will likely re-use the same crank in the m235, m4 and m2. The only difference is that the m4 doesnt have the increment wheel on the crank which likely explains the 4lb weight difference. There would be no point for them to recreate another crank.

[N54B30A]

Originally Posted by BruceM

That is certainly my hope. That way, you make the M2 a better 1M, not a better M4....

The way I see it, the m2 likely has the strongest block out of all of the turbo i6's. You get the rigidity of both a closed deck and cast in iron sleeves which is far stronger than the tiny .3mm thick LDS coating.

[zenmaster]

Originally Posted by sahyoun

That would make sense if the m4 used a magnesium alloy crank. The crank in the m4 is a steel alloy, theres absolutely no magnesium in it. You may be thinking of the oil pan. The M4's crank uses 42CrMoS4 steel alloy found here: http://www.steelnumber.com/en/steel_...hp?name_id=195

Magnesium is not even close to an ideal alloy for load bearing engine internals. Where did you hear that its using the m235i's crank? Theres no information I could find on that...

They will likely re-use the same crank in the m235, m4 and m2. The only difference is that the m4 doesnt have the increment wheel on the crank which likely explains the 4lb weight difference. There would be no point for them to recreate another crank.

Good catch on the lack of magnesium, I recalled incorrectly what the alloy was and assumed magnesium due to weight difference. I also assumed S55 crank was not used due to the 4lb weight difference which is non trivial.

[N54B30A]

Originally Posted by zenmaster

Good catch on the lack of magnesium, I recalled incorrectly what the alloy was and assumed magnesium due to weight difference. I also assumed S55 crank was not used due to the 4lb weight difference which is non trivial.

Yeah, seems like bmw likes to hide these things.

[zenmaster]

Originally Posted by sahyoun

They will likely re-use the same crank in the m235, m4 and m2.

Apparently the M2 uses the exact same crank as the M235i:

From the a review, "The engineer tells us that the crankshaft is the same as in the M 235i, because it is more stable and of a sturdier construction than the one in the N55..."

Although not sure what N55 he means.

[Reapur]

I'm sorry but nowhere can I find any information saying that the engine in the M2 is based off the S55 basic casting and block. Or that it's of a closed deck design.

On the contrary BMWs own product technical data states that it is a further development of the N55. And I quote:

"The N55B30T0 engine is the power plant for the F87 BMW M2. It is a further development of the N55B30O0 engine from the BMW M135i and BMW M235i, which is familiar from the current BMW 1 Series and 2 Series models."

As you can see clearly there are very little similarities between the block found in the S55 and N55:

S55 top and N55 bottom

[BMWPWR]

Originally Posted by Reapur

I'm sorry but nowhere can I find any information saying that the engine in the M2 is based off the S55 basic casting and block. Or that it's of a closed deck design.

On the contrary BMWs own product technical data states that it is a further development of the N55. And I quote:

"The N55B30T0 engine is the power plant for the F87 BMW M2. It is a further development of the N55B30O0 engine from the BMW M135i and BMW M235i, which is familiar from the current BMW 1 Series and 2 Series models."

As you can see clearly there are very little similarities between the block found in the S55 and N55:

S55 top and N55 bottom

M In Every Sense.
One look under the hood of the BMW M2 and there's no doubt it's an M. A fully aluminum closed-deck block design and grey-cast iron liners allow cylinders to endure higher pressure under the most demanding driving conditions, while lightweight components and a forged crankshaft allow immediate throttle response.

Quoted from:

http://m.bmwusa.com/#m2LP

[dammitcubs]

I'm starting to notice that every single video - he makes a note to everyone that he's a "Lotus guy".

LOL - okay we get it.

[TomAce]

Originally Posted by dammitcubs

I'm starting to notice that every single video - he makes a note to everyone that he's a "Lotus guy".

LOL - okay we get it.

What a clown...

[PrematureApex]

Originally Posted by Reapur

I'm sorry but nowhere can I find any information saying that the engine in the M2 is based off the S55 basic casting and block. Or that it's of a closed deck design.

On the contrary BMWs own product technical data states that it is a further development of the N55. And I quote:

"The N55B30T0 engine is the power plant for the F87 BMW M2. It is a further development of the N55B30O0 engine from the BMW M135i and BMW M235i, which is familiar from the current BMW 1 Series and 2 Series models."

As you can see clearly there are very little similarities between the block found in the S55 and N55:

S55 top and N55 bottom

Well you didn't look very hard. Multiple sources...

http://www.bmwusa.com/standard/conte...rience/m2.aspx

One look under the hood of the BMW M2 and there's no doubt it's an M. A fully aluminum closed-deck block design and grey-cast iron liners allow cylinders to endure higher pressure under the most demanding driving conditions, while lightweight components and a forged crankshaft allow immediate throttle response.

Edit: Sorry, didn't see it was already posted.

Your pic is the regular N55 block. Odds are, BMW wouldn't make 2 closed deck, N55-based blocks. The M2's N55 likely usse the same base S55 casting, but gets liners vs. the more expensive arc coating of the S55.

[PrematureApex]

Originally Posted by TomAce

What a clown...

Best username ever btw...

[PrematureApex]

Originally Posted by zenmaster

Although not sure what N55 he means.

The cast crank from the standard N55 engines (not the M235's).

[ed4]

"Saul Goodman Reviews New BMW M2"

[PrematureApex]

Originally Posted by sahyoun

Yeah, the word rod wasn't even mentioned so who knows. In terms of having a car to keep and mod, the m2 just seems like a deal of a lifetime. You can always upgrade the cooling and turbos to be equal to or better than the m4. Not to mention it has a hell of a lot more block rigidity considering its got massive iron sleeves. I wonder what the differences in the head are.

Originally Posted by BruceM

That is certainly my hope. That way, you make the M2 a better 1M, not a better M4....

I mean, can't imagine anyone making a twin turbo conversion...so the N55 will never have the twins of the N54 and S55...

[miiipilot]

Originally Posted by raysspl

Never really a fan of any of the motoman reviews...

Me too! i am already anxious. Thanks for the extra anxiety, motoman!