[tn508s]

Thoughts and opinions on this?

I know the b58 is a better engine which makes me wonder why they put an n55 in the f87 m2.

[jzeiler4]

Actually the new M2 has the S55 engine.

[tn508s]

Originally Posted by jzeiler4

Actually the new M2 has the S55 engine.

The 2020 version?

[M3SQRD]

Originally Posted by tn508s

The 2020 version?

The N55 was used in the F87 M2 from 2016-2018. The B58 wasn’t available when the M2 development initially started back in ~2013-2014. The B58 was introduced in MY 2016 in the F30 340i.

The S55 was used in the F87 M2 Competition from 2018-2021.

The S55 was used in the F87 M2CS for 2020.

[tn508s]

Originally Posted by M3SQRD

The N55 was used in the F87 M2 from 2016-2018. The B58 wasn’t available when the M2 development initially started back in ~2013-2014. The B58 was introduced in MY 2016 in the F30 340i.

The S55 was used in the F87 M2 Competition from 2018-2021.

The S55 was used in the F87 M2CS for 2020.

So as a b58 guy why is this such a better engine?

[tn508s]

Originally Posted by M3SQRD

The N55 was used in the F87 M2 from 2016-2018. The B58 wasn’t available when the M2 development initially started back in ~2013-2014. The B58 was introduced in MY 2016 in the F30 340i.

The S55 was used in the F87 M2 Competition from 2018-2021.

The S55 was used in the F87 M2CS for 2020.

There's a guy on YouTube "thic whips" do you know what his car is?

[Kernel Kurtz]

I don't think there was a B58 when M2s had the N55. AFAIK they went from N55 to S55 to S58, which seems like a normal progression of updates over time to me.

[M3SQRD]

Originally Posted by tn508s

There's a guy on YouTube "thic whips" do you know what his car is?

I do not. Do you know if it’s a Competition or CS? If it isn’t then it’ll have a N55 engine whereas, if it’s one of those, then it’ll have a S55.

Edit - from a quick look, I think he has a N55. His dash shows a 7k rpm redline which is the N55 redline. However, I could be wrong.

[tn508s]

Originally Posted by Kernel Kurtz

I don't think there was a B58 when M2s had the N55. AFAIK they went from N55 to S55 to S58, which seems like a normal progression of updates over time to me.

I didn't have this much knowledge. Now I know.

So say the year 2015, my 235 had a n55, what did the 240 and the m2 have?

[tn508s]

Originally Posted by M3SQRD

I do not. Do you know if it’s a Competition or CS? If it isn’t then it’ll have a N55 engine whereas, if it’s one of those, then it’ll have a S55.

Edit - from a quick look, I think he has a N55. His dash shows a 7k rpm redline which is the N55 redline. However, I could be wrong.

I don't but in the last 4 days I've frequented his videos on all of my lunch and coffee breaks... very good content 👌 he goes through tunes like bm3 step by step and I've learned alot. I coulda swore I heard "m2" and "n55" a couple of times. And I know he said his stock hp was 320 which is the same as my n55.

[Kernel Kurtz]

Originally Posted by tn508s

I didn't have this much knowledge. Now I know.

So say the year 2015, my 235 had a n55, what did the 240 and the m2 have?

The 240 is the replacement for the 235. I think the 235 has the N55 and the 240 has the B58. The M2 has a different lifecycle all its own.

[tn508s]

Originally Posted by Kernel Kurtz

The 240 is the replacement for the 235. I think the 235 has the N55 and the 240 has the B58. The M2 has a different lifecycle all its own.

Ohhh, I didn't realize it worked like that. I thought there was a 220, 228, 230, 235, 240, every year and each was just a step up in size.

[M3SQRD]

Originally Posted by tn508s

I didn't have this much knowledge. Now I know.

So say the year 2015, my 235 had a n55, what did the 240 and the m2 have?

The 240 replaced the 235 in 2017. So the M240i/ix was released as a MY 2017 with a B58.

The F87 M2 was released in 2016 with the N55. The M2 used the N55 from 2016-2018. When the F87 M2 Competition was released in 2018 it had the S55 engine which was used until the end of production of the F87 M2 Competition in 2021.

[Kernel Kurtz]

Originally Posted by tn508s

Ohhh, I didn't realize it worked like that. I thought there was a 220, 228, 230, 235, 240, every year and each was just a step up in size.

It's actually complicated and not entirely intuitive, however the 340 is also the replacement for the 335 and the 230 is the replacement for the 228. That said the 2 series is the replacement for the 1 series 128 and 135 (at least in North America). The 3 series used to have coupes and sedans, but the sedans are 3 series and the coupes are 4 series now, except for the Gran Coupes LOL. They still have an M140i in Europe. I'd like one.

So yeah, its hard to keep track of, especially when you also get into 5's and 6's and 7's and '8s and x's and i's and M's. And then there are the diesels as well.

[tn508s]

Originally Posted by Kernel Kurtz

It's actually complicated and not entirely intuitive, however the 340 is also the replacement for the 335 and the 230 is the replacement for the 228. That said the 2 series is the replacement for the 1 series 128 and 135. The 3 series used to have coupes and sedans, but the sedans are 3 series and the coupes are 4 series now.

So yeah, its hard to keep track of, especially when you also get into 5's and 6's and 7's and '8s and x's and i's and M's.

Jesus, just when I thought I was catching on.

[flybywire]

it started out OK where the last two digits were basically the engine displacement in liters, but at some point BMW decided that it was more of a relative power scale than an actual measurement. So, a 240 (with B58) has the same displacement as a 235 (with N55), but makes more power so gets a bigger number.

[celsdogg]

BMW USA (not sure what BMW Canada does) usually brings over 2 motors for the each series of vehicles. Usually during the middle of a models life, they replace both motors with newer power units so it helps to follow the lifecycle of different motors too.

While both have the N55, they have different version of it. The M235i has the N55B30O0 while the OG M2 had the N55B30T0, which I believe was the only bimmer to receive this iteration of the N55 (edit: the F26 X4 also had the T0).

Here is a link to a FCP article with the differences:
https://blog.fcpeuro.com/the-definit...specs-upgrades

[M3SQRD]

Originally Posted by tn508s

So as a b58 guy why is this such a better engine?

I’m not a b58 guy, I’m really an s65 guy who just happens to have s55, b58 and b48 engines

The n55 and b58 engines are both 3.0L single turbo I6 engines. The B58 has the advantage of learning from two other BMW turbocharged I6s - the n54 and n55 engines. The b58 has several improvements over the n55 such as a forged steel crankshaft, a closed deck block and an improved fuel system. These changes make the b58 more reliability than the n55 which had an open deck block, a cast crankshaft, and a weaker charge pipe setup. However, the n55 is a much freer revving engine and sounds better (less restricted exhaust setup), although sound quality is a subjective thing. In terms of tuning potential, the b58, due to its forged crank and closed deck, is capable of handling higher boost levels and, therefore, higher horsepower and torque output.

[XutvJet]

Originally Posted by M3SQRD

The b58 has several improvements over the n55 such as a forged steel crankshaft, a closed deck block and an improved fuel system. These changes make the b58 more reliability than the n55 which had an open deck block, a cast crankshaft, and a weaker charge pipe setup. However, the n55 is a much freer revving engine and sounds better (less restricted exhaust setup), although sound quality is a subjective thing. In terms of tuning potential, the b58, due to its forged crank and closed deck, is capable of handling higher boost levels and, therefore, higher horsepower and torque output.

The N55 in M235 and M2 have forged cranks. All other N55s do not. All EWG equipped N55s (mostly beginning in 2014) have S55 forged rods and the S55 rod bearings which are way better than the prior parts used in the earlier PWG N55s.

The open deck of the N55 isn't an issue unless you have plans to push 600whp+.

Same goes for fueling. Unless you plan to push 400whp+, fueling isn't an issue. Luckily, it's a cheap fix if you need the capacity.

The main reason BMW went with the N55 in the 2016-2018 was because the B58 did not meet their requirements for track usage, specifically oiling under high Gs. The N55 in the M2 has the S55 oil pump and sump system allows the motor to handle sustained high G loads. Many of the S55 parts are interchangeable with the N55, but not the B58 as it's an entirely difference generation of motor.

The reason the B58 uses a closed deck block is not because of all out power potential, but rather it's the same block used in the diesel variants. The block of the B58 is super stout, but other expensive internal parts need replacing if you want to push 600whp in the B58 over the long term. The B58, just like the N55 or N54, aren't designed for huge power like so many try to push through. The S55s and S58s are specifically designed to handle big power.

The N55 in the M2 weakest link is intercooling on the track. If you plan to track these cars, a larger intercooler is a must. Cheap and easy fix.

[M3SQRD]

Originally Posted by XutvJet

The N55 in M235 and M2 have forged cranks. All other N55s do not. All EWG equipped N55s (mostly beginning in 2014) have S55 forged rods and the S55 rod bearings which are way better than the prior parts used in the earlier PWG N55s.

The open deck of the N55 isn't an issue unless you have plans to push 600whp+.

Same goes for fueling. Unless you plan to push 400whp+, fueling isn't an issue. Luckily, it's a cheap fix if you need the capacity.

The main reason BMW went with the N55 in the 2016-2018 was because the B58 did not meet their requirements for track usage, specifically oiling under high Gs. The N55 in the M2 has the S55 oil pump and sump system allows the motor to handle sustained high G loads. Many of the S55 parts are interchangeable with the N55, but not the B58 as it's an entirely difference generation of motor.

The reason the B58 uses a closed deck block is not because of all out power potential, but rather it's the same block used in the diesel variants. The block of the B58 is super stout, but other expensive internal parts need replacing if you want to push 600whp in the B58 over the long term. The B58, just like the N55 or N54, aren't designed for huge power like so many try to push through. The S55s and S58s are specifically designed to handle big power.

The N55 in the M2 weakest link is intercooling on the track. If you plan to track these cars, a larger intercooler is a must. Cheap and easy fix.

Thanks for the detailed response. Like I said I’m a S65 guy and, tbh, I know very little about the N54 and N55 engines. My experience is primarily with S engines - s50, s54, s65 and s55. Also, experience with the M54, N20, B58 and B46. My B58 and B46 engines are stock and will remain stock.

[mecheng77]

Originally Posted by XutvJet

The N55 in M235 and M2 have forged cranks. All other N55s do not. All EWG equipped N55s (mostly beginning in 2014) have S55 forged rods and the S55 rod bearings which are way better than the prior parts used in the earlier PWG N55s.

The open deck of the N55 isn't an issue unless you have plans to push 600whp+.

Same goes for fueling. Unless you plan to push 400whp+, fueling isn't an issue. Luckily, it's a cheap fix if you need the capacity.

The main reason BMW went with the N55 in the 2016-2018 was because the B58 did not meet their requirements for track usage, specifically oiling under high Gs. The N55 in the M2 has the S55 oil pump and sump system allows the motor to handle sustained high G loads. Many of the S55 parts are interchangeable with the N55, but not the B58 as it's an entirely difference generation of motor.

The reason the B58 uses a closed deck block is not because of all out power potential, but rather it's the same block used in the diesel variants. The block of the B58 is super stout, but other expensive internal parts need replacing if you want to push 600whp in the B58 over the long term. The B58, just like the N55 or N54, aren't designed for huge power like so many try to push through. The S55s and S58s are specifically designed to handle big power.

The N55 in the M2 weakest link is intercooling on the track. If you plan to track these cars, a larger intercooler is a must. Cheap and easy fix.

Well said. So stock for stock there isn’t much difference betweeen the two. Yes the b58 has more power but it also has a difficult to access timing chain and vanos if something goes wrong and yes the N55 sounds much better. Open vs closed deck doesn’t matter day to day until you tune it.

If you plan to track it, yes the N55 can suffer in tight turns but the N55-M2 solved that.

I’m not sure how good the B58 oiling system is, can someone chime in?

There are many high mileage N55 engines, especially with the updated bearings

[Nickies]

Is there any report of timing chain failure on the B58? This seems to be terribly expensive to service.