[Yellowflash21]

It just might be that whole unit had to be redesigned for X model.

But it was expected that turbo was completely different compared to M235i.

They just created such a public confusion by giving N55 name to an M car.

[FSociety]

Originally Posted by Nantucket

So the M2 turbo is also different than the X4 M40i turbo?

Yes because the M2 has overboost feature of 370lb torque, so in essence the X4 M40i engine is a detuned M2 (355hp/343).

[zenmaster]

Originally Posted by Nantucket

So the M2 turbo is also different than the X4 M40i turbo?

Yes, which reinforces that M2 actually has a custom turbo as opposed to another iteration of N55 turbo.

[zenmaster]

Originally Posted by Yellowflash21

They just created such a public confusion by giving N55 name to an M car.

they've done it before!

[Yellowflash21]

Interested to hear about their previous failures.

[PrematureApex]

Originally Posted by zenmaster

they've done it before!

When?

The N54 in the 1M was literally an N54, same as the prior year 1/3 335.. No hardware changes.

BMW's marketing department must have serious hand getting this engine named an N55. Different block? Different pistons? Different turbo? Never, in BMW's history, have such changes not resulted in a primary designation change. Not that I think a name matters at all, but you can see how the mouthbreathers react to the N55 label.

Best performance buy from a straight line/tuning perspective? An '08-'10 135 or '07-'10 335. Honestly, when it's all said and done, I bet there are many people who wish the M2 just got a carry-over engine from the 1M.

[zenmaster]

Originally Posted by PrematureApex

When?

The N54 in the 1M was literally an N54, same as the prior year 1/3 335.. No hardware changes.

You win the prize, the N54 with the 1M!

[rosenbergendo]

Hello Stage 1 tune with big numbers with this turbo!

[PackPride85]

M235 turbo part #: 11 65 7 636 424
M2 turbo part #: 11 65 8 053 153

[FSociety]

Originally Posted by PackPride85

M235 turbo part #: 11 65 7 636 424
M2 turbo part #: 11 65 8 053 153

thank you

[imported_Riq]

M2 has a different turbo, based on the HP and power band.

The M2 makes peak HP @ 6500 rpms ; vs. X4 40M @ 5800 RPMs. Same for the M235i; peak HP in the 6000 rpms.

I don't see how the M2 could have this kind of power & power band without a bigger turbo.

Granted camshafts have something to do with the power band, but in order to make HP you need to make boost on the upper RPM range.

[FSociety]

Originally Posted by Thurman Murch

It's the same turbo as M235i

M2 has better integrated turbo into ex manifold for rapid warm up, top piston ring from M3, same spark plugs, bigger injectors, forged steel crank, same bearings as M3, same but single air intake like M3 with m sport hole at bottom of air box

The B series version would use:

11658637041

BMW, give me B58 instead!

[zenmaster]

S58 with that water injecting thingy

[SeanWRT]

Originally Posted by FSociety

BMW, give me B58 instead!

Better stick to high rev N55 but with the slightly bigger B58 turbo, or simply enlarge N55 turbo's compressor end, anything that makes better flow. That's what I've always been thinking.

When it comes to m car, I believe the shorter N55's higher rev capability will make up for its loss at low down to B58. Though future M for sure will adopt longer block design of B series engine found in more eco-focused regular 3/4ers.

Tuners probably can increase B58's rpm to match N55 and will see considerably better results (longer block means bigger torque, which is physics), but in doing that, B58's structural integrity will be compromised due to higher piston speed (piston travels longer and faster at given rpm, the impact is significantly greater, which is physics) and engine will be mechanically less efficient (rods & crank being less close to being 90% angle in a complete stroke), compared to its short block counterpart.

[bradsm87]

Nobody thought to check 335i part number?

M235i part number is different for whatever reason but M2 and 335i are the same part number. M2 does not have a bigger turbo.

[Glounk]

I'm very happy with the small turbo stick to the N55 in the M2 wich gives it a straight rev almost like a NA engine!!!! I wouldn't be a customer for a biturbo like in the M3/4, not for me at all, she is perfect ;-)

[zenmaster]

You get the faster spooling, but the turbo is working too hard, which contributes undesirable heat.

[kiysersosae]

Originally Posted by zenmaster

You get the faster spooling, but the turbo is working too hard, which contributes undesirable heat.

I confirm this, check out the iAT on my car... It started at 22degC at 2000rpm. Ignore the timing it was at 2deg from about 4500rpm, I must have just lifted off when I captured this shot.

[FSociety]

Desperately needs Meth cooling