[6SpeedCrewCab]

I know that there are several variations of the n55 that we're used for different applications. For example, I know my f30 pre-LCI 335i uses the n55b30m0 and is advertised as having ~300hp but has been shown to make 270-285whp on a dyno.
I was curious about the other variations such as the n55b30o0 and the n55b30t0 that are used in the m235i and the M2 as well as any others out there.
What are their advertised numbers and what have they put down on the dyno in stock form?
What physical parts change between them and what is changed on the stock maps?

[Munchi435i]

Originally Posted by mmsharp

I know that there are several variations of the n55 that we're used for different applications. For example, I know my f30 pre-LCI 335i uses the n55b30m0 and is advertised as having ~300hp but has been shown to make 270-285whp on a dyno.
I was curious about the other variations such as the n55b30o0 and the n55b30t0 that are used in the m235i and the M2 as well as any others out there.
What are their advertised numbers and what have they put down on the dyno in stock form?
What physical parts change between them and what is changed on the stock maps?

N55 M2 - has forged internals

thats about all i know about it but they all make the same Crank HP

[doodlebro]

N55 M2 is the highest spec. X4 M40i shares some similarities like the closed deck block and maybe pistons/rods, but you have to do a part by part comparison to see what matches and what was only for the M2.

Medium spec N55 is what's in my X3, which doesn't have anything crazy fancy but can be reliable up to 400-450 whp with proper maintenance.

[Pray for Mojo]

M2 has same block, forged crank and rods, and different pistons. M235i has forged crank and rods, but different pistons from M2.

[bradsm87]

There are exceptions but:

N55B30M0 (PWG and EWG) - 225kw (335i, 535i)
N55B30O0 (PWG) - 235kw (early M135i, 640i)
N55B30O0 (EWG) - 240kw (late M135i, late 640i, M235i, late 335i PPK, late 535i PPK)
N55B30T0 (EWG) - 272kw (M2)

I don't know or care which ones are in which SUVs so they're not listed.

There are hardware differences between PWG and EWG. There aren't hardware differences between N55B30M0 and N55B30O0. Only tuning. N55B30T0 has some hardware changes.

[6SpeedCrewCab]

Originally Posted by doodlebro

N55 M2 is the highest spec. X4 M40i shares some similarities like the closed deck block and maybe pistons/rods, but you have to do a part by part comparison to see what matches and what was only for the M2.

Medium spec N55 is what's in my X3, which doesn't have anything crazy fancy but can be reliable up to 400-450 whp with proper maintenance.

I plan on making somewhere around 400-450whp so that's good to know. Do you know if a clutch upgrade is required to hold that much power?

[6SpeedCrewCab]

Originally Posted by bradsm87

There are exceptions but:

N55B30M0 (PWG and EWG) - 225kw (335i, 535i)
N55B30O0 (PWG) - 235kw (early M135i, 640i)
N55B30O0 (EWG) - 240kw (late M135i, late 640i, M235i, late 335i PPK, late 535i PPK)
N55B30T0 (EWG) - 272kw (M2)

I don't know or care which ones are in which SUVs so they're not listed.

There are hardware differences between PWG and EWG. There aren't hardware differences between N55B30M0 and N55B30O0. Only tuning. N55B30T0 has some hardware changes.

My 335i came with the M power pack from the factory which I assume is what they do to the stock n55b30o0, correct?

[doodlebro]

Originally Posted by mmsharp

I plan on making somewhere around 400-450whp so that's good to know. Do you know if a clutch upgrade is required to hold that much power?

It's more of a torque down low question, power in the mid-range and up-top should not slip a clutch, but if you're planning on launching the vehicle you definitely want to upgrade it.

[XutvJet]

Originally Posted by doodlebro

N55 M2 is the highest spec. X4 M40i shares some similarities like the closed deck block and maybe pistons/rods, but you have to do a part by part comparison to see what matches and what was only for the M2.

Medium spec N55 is what's in my X3, which doesn't have anything crazy fancy but can be reliable up to 400-450 whp with proper maintenance.

FYI to the group, there is no closed deck N55.

[enemigo13]

Originally Posted by Pray for Mojo

M2 has same block, forged crank and rods, and different pistons. M235i has forged crank and rods, but different pistons from M2.

it's not true of course. connecting rod part no is the same starting from e90 LCI ending F8x S55, of course including M2 and M235i.

[enemigo13]

Originally Posted by bradsm87

There are exceptions but:
There aren't hardware differences between N55B30M0 and N55B30O0. Only tuning. N55B30T0 has some hardware changes.

it's not true of course. N55B30O0 and N55B30T0 have different crankshaft vs N55B30M0.

[bradsm87]

Originally Posted by enemigo13

it's not true of course. N55B30O0 and N55B30T0 have different crankshaft vs N55B30M0.

Sometimes but not always. PPK is considered N55B30O0 in all of the DME files for example. I'm not conviced that all O0 has a forged crank and all m0 don't. I haven't crawled through realoem to prove one way or the other.

[enemigo13]

yes, I understand what you mean, but I mean O0 from the factory like M235i, 640i etc,I have no info crankshaft is forged or not (did not find info about it in M2 technical training pdf) but the fact it is different from 306hp versions.

Originally Posted by bradsm87

Sometimes but not always. PPK is considered N55B30O0 in all of the DME files for example. I'm not conviced that all O0 has a forged crank and all m0 don't. I haven't crawled through realoem to prove one way or the other.

[ChristosD]

This is a crank from a 2014 m235i (spun bearings not my car )
this car has the N55B30O0. to me this crank looks cast and not forged

[ceedawg]

I am reaching the point where it is quite possible that ALL the N55 engines share the same parts. By the way someone I believe confirmed open deck block on ALL N55 motors.
Went through this also with the MB and MB AMG M113 motor 4.3,5.0,5.4L. One group says forged parts but when you break the motors down on a bench you find hardware for each M113 motor is made out of the same material. Exception M113K the Kompressor motor has different pistons and rods.

[CandyRedRC46]

Originally Posted by ChristosD

This is a crank from a 2014 m235i (spun bearings not my car )
this car has the N55B30O0. to me this crank looks cast and not forged

All Honda cranks are factory forged, from the lowest spec D-seres all the way up through the type R's. This crank looks no different than any Honda crank that I have seen.

[doodlebro]

Originally Posted by ceedawg

I am reaching the point where it is quite possible that ALL the N55 engines share the same parts. By the way someone I believe confirmed open deck block on ALL N55 motors.
Went through this also with the MB and MB AMG M113 motor 4.3,5.0,5.4L. One group says forged parts but when you break the motors down on a bench you find hardware for each M113 motor is made out of the same material. Exception M113K the Kompressor motor has different pistons and rods.

Not quite, I have done some minor comparison in realOEM, and the M2 has a different crank as well as different pistons than my X3's N55. This is purely based on different part numbers.

[enemigo13]

yes M2 pistons are from S55 engine, just different rings as M2 liners are cast iron while S55 LDS coated. N55 had many iterations starting from E series N55, ending with M2, many hardware changes: injectors, turbos, downpipes, crankshafts, high pressure fuel pumps etc.

Originally Posted by doodlebro

Not quite, I have done some minor comparison in realOEM, and the M2 has a different crank as well as different pistons than my X3's N55. This is purely based on different part numbers.

[ceedawg]

Originally Posted by doodlebro

Not quite, I have done some minor comparison in realOEM, and the M2 has a different crank as well as different pistons than my X3's N55. This is purely based on different part numbers.

I will not go strictly by part numbers when it comes to engines in the same family. This can also be true with transmission parts for these cars as well. Yes years can vary with different parts it is a real mess Like I said
I have seen this with MB/AMG . The only true and accurate way to confirm what you have is when you have the actual motors from the different cars broken down right in front of your face. M235,335i,M2 let me see an actual motor broken down and each part compared. You will be surprised to find out how the different part numbers can actually be for the same part and sometimes depending on year. Some part numbers become discontinued and they will give a totally different part number for the same exact part. Happens to Engine parts,tranny parts and even suspension parts.

I have seen this with M50,52,S50,52 motors in the E36. Many interchangeable parts ,some with different part #s but the exact same part.

Just to throw this they also have an aluminum block M52 motor and a cast iron M52 block. Lots of folks did not know this. I always like to see the motors in person before the car maker starts spewing out differences for marketing purposes. Sometimes they are correct and sometimes the info is way off.

[XutvJet]

The M235 and M2 share crank part numbers. The other N55's have a different number and there is no note in realoem that the number has been superceded.

All N55s have the same forged rods as the S55 if it makes you sleep better at night.

No N55s, N54s, or S55s have forged pistons. They're all hyperutetic. It's very rare that factory motors have forged pistons due to emissions requirements, long term reliability, and NVH goals.

[XutvJet]

Originally Posted by ChristosD

This is a crank from a 2014 m235i (spun bearings not my car )
this car has the N55B30O0. to me this crank looks cast and not forged

That is a forged crank.

[enemigo13]

for unknown reasons you're confusing superseded and just different parts. e.g. maybe you will remove M2 turbo, then compare with usual N55 ewg turbo and will report - guys, part numbers are different but I've checked turbine/compressor wheels dimensions - they're actually the same turbos! But they're not. Difference is in manifold and N55 turbo comes together with the manifold, that's why M2 turbo has another part no.

Originally Posted by ceedawg

I will not go strictly by part numbers when it comes to engines in the same family. This can also be true with transmission parts for these cars as well. Yes years can vary with different parts it is a real mess Like I said
I have seen this with MB/AMG . The only true and accurate way to confirm what you have is when you have the actual motors from the different cars broken down right in front of your face. M235,335i,M2 let me see an actual motor broken down and each part compared. You will be surprised to find out how the different part numbers can actually be for the same part and sometimes depending on year. Some part numbers become discontinued and they will give a totally different part number for the same exact part. Happens to Engine parts,tranny parts and even suspension parts.

I have seen this with M50,52,S50,52 motors in the E36. Many interchangeable parts ,some with different part #s but the exact same part.

Just to throw this they also have an aluminum block M52 motor and a cast iron M52 block. Lots of folks did not know this. I always like to see the motors in person before the car maker starts spewing out differences for marketing purposes. Sometimes they are correct and sometimes the info is way off.