BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read
M2 Technical Topics > N55 Engine / Drivetrain / Exhaust / Bolt-ons / Tuning > Tuned N55 crank hub issues

Post Reply
 
Thread Tools Search this Thread
      12-31-2019, 09:05 AM   #1
Msm1984
Second Lieutenant
Msm1984's Avatar
United_States
130
Rep
232
Posts

Drives: 16 M4
Join Date: Nov 2019
Location: Miami

iTrader: (1)

Tuned N55 crank hub issues

Curious if anyone has ever heard of a N55 crank hub spinning? Now that I am back in my og M2 I am contemplating doing some preventive maintenance, but I can't find anyone who has ever had an issue. Has anyone else heard anything?
__________________
08 E92 M3
16 M4
17 M2
17 M4 ZCP
18 M4 ZCP ( Current )
Appreciate 0
      12-31-2019, 09:18 AM   #2
hlm2c
Lieutenant
United_States
290
Rep
408
Posts

Drives: M2C
Join Date: Dec 2018
Location: US/Korea

iTrader: (1)

Even though the N55 runs the same crank hub design as the S55, the N55 doesn't produce enough power to cause a spun crank hub. Good piece of mind to have lol.
Appreciate 0
      12-31-2019, 02:11 PM   #3
F87source
Major General
F87source's Avatar
No_Country
7178
Rep
7,343
Posts

Drives: Bmw M2
Join Date: Aug 2018
Location: .

iTrader: (1)

Quote:
Originally Posted by hlm2c View Post
Even though the N55 runs the same crank hub design as the S55, the N55 doesn't produce enough power to cause a spun crank hub. Good piece of mind to have lol.
Not entirely the when story...

Power might not be the only relevant factor, if the hub spins it can spin at any power level and any rpm in the s55. The n54 shares the same hub and most tuned N54's and even high power turbo upgrade ones don't see the spinning hub issue. The only case I have heard was the VTT car, but they announced that as soon as they made their CBC so take that as you will... They could be a very rare case because they do make an exceptionally high amount of power.


I think the s55 spins easier due to a few features: the timing system drives two hpfps instead of one, the timing system also drives a larger oil pump, timing system also drives a water pump which is not electric on the s55, and the dct down shifts alot harder than non dct equipped N54's and n55's. This makes some sense since the s55's have been reported to spin even while cruising.


I've also seen higher horse power s55's soon easier than non s55 cars, though there has been a lot of debate as to why.
__________________
Click on the link below to see a compiled list of every review I have ever written:
https://f87.bimmerpost.com/forums/sh...2#post30368242
Appreciate 0
      01-07-2020, 07:55 PM   #4
Msm1984
Second Lieutenant
Msm1984's Avatar
United_States
130
Rep
232
Posts

Drives: 16 M4
Join Date: Nov 2019
Location: Miami

iTrader: (1)

Quote:
Originally Posted by F87source View Post
Quote:
Originally Posted by hlm2c View Post
Even though the N55 runs the same crank hub design as the S55, the N55 doesn't produce enough power to cause a spun crank hub. Good piece of mind to have lol.
Not entirely the when story...

Power might not be the only relevant factor, if the hub spins it can spin at any power level and any rpm in the s55. The n54 shares the same hub and most tuned N54's and even high power turbo upgrade ones don't see the spinning hub issue. The only case I have heard was the VTT car, but they announced that as soon as they made their CBC so take that as you will... They could be a very rare case because they do make an exceptionally high amount of power.


I think the s55 spins easier due to a few features: the timing system drives two hpfps instead of one, the timing system also drives a larger oil pump, timing system also drives a water pump which is not electric on the s55, and the dct down shifts alot harder than non dct equipped N54's and n55's. This makes some sense since the s55's have been reported to spin even while cruising.


I've also seen higher horse power s55's soon easier than non s55 cars, though there has been a lot of debate as to why.
Quote:
Originally Posted by F87source View Post
Quote:
Originally Posted by hlm2c View Post
Even though the N55 runs the same crank hub design as the S55, the N55 doesn't produce enough power to cause a spun crank hub. Good piece of mind to have lol.
Not entirely the when story...

Power might not be the only relevant factor, if the hub spins it can spin at any power level and any rpm in the s55. The n54 shares the same hub and most tuned N54's and even high power turbo upgrade ones don't see the spinning hub issue. The only case I have heard was the VTT car, but they announced that as soon as they made their CBC so take that as you will... They could be a very rare case because they do make an exceptionally high amount of power.


I think the s55 spins easier due to a few features: the timing system drives two hpfps instead of one, the timing system also drives a larger oil pump, timing system also drives a water pump which is not electric on the s55, and the dct down shifts alot harder than non dct equipped N54's and n55's. This makes some sense since the s55's have been reported to spin even while cruising.


I've also seen higher horse power s55's soon easier than non s55 cars, though there has been a lot of debate as to why.


This makes sense. I have yet to find one single person who has ever spun the crank hub on an N55 even when running PS2. I have seen a couple of cases where this happened on N54 but the power levels were just insane and still it seems to be extremely rare. Do you think the this could also be due to being a true twin turbo vs just a twin scroll?
__________________
08 E92 M3
16 M4
17 M2
17 M4 ZCP
18 M4 ZCP ( Current )
Appreciate 0
      01-07-2020, 08:54 PM   #5
F87source
Major General
F87source's Avatar
No_Country
7178
Rep
7,343
Posts

Drives: Bmw M2
Join Date: Aug 2018
Location: .

iTrader: (1)

Quote:
Originally Posted by Msm1984 View Post
This makes sense. I have yet to find one single person who has ever spun the crank hub on an N55 even when running PS2. I have seen a couple of cases where this happened on N54 but the power levels were just insane and still it seems to be extremely rare. Do you think the this could also be due to being a true twin turbo vs just a twin scroll?
Turbo setup shouldn't have any effect, it could be possible if it was supercharged as it would be belt driven off the crank but since that's not the case as twin charged cars are so rare even outside of the bmw world that discussion should be irrelevant.

Anyways no imo being a twin turbo car vs. single turbo shouldn't have much of an effect if any.

Edit- twins could allows for faster spooling and more power down low when upgrading to larger turbos, but any effect would be minimal and shouldn't contribute to spinning the hub imo.
__________________
Click on the link below to see a compiled list of every review I have ever written:
https://f87.bimmerpost.com/forums/sh...2#post30368242
Appreciate 0
      01-09-2020, 11:38 AM   #6
Anthony1s
Banned
756
Rep
2,149
Posts

Drives: 2018 Mineral Grey M2
Join Date: Oct 2017
Location: Pennsylvania

iTrader: (0)

I did see a TSB for the N55 bedplate. I didn't look into it much, so I don't know what model years it's for. But I remember someone said it's related to the crank hub.

EDIT: here is what I'm talking about.

Appreciate 0
      01-10-2020, 03:19 AM   #7
F87source
Major General
F87source's Avatar
No_Country
7178
Rep
7,343
Posts

Drives: Bmw M2
Join Date: Aug 2018
Location: .

iTrader: (1)

Quote:
Originally Posted by Anthony1s View Post
I did see a TSB for the N55 bedplate. I didn't look into it much, so I don't know what model years it's for. But I remember someone said it's related to the crank hub.

EDIT: here is what I'm talking about.

Interesting, ive heard of the new bed plate design for the S55 awhile back but I don't recall the year.

Btw where do you get TSB info from?
__________________
Click on the link below to see a compiled list of every review I have ever written:
https://f87.bimmerpost.com/forums/sh...2#post30368242
Appreciate 0
      01-10-2020, 09:54 AM   #8
Anthony1s
Banned
756
Rep
2,149
Posts

Drives: 2018 Mineral Grey M2
Join Date: Oct 2017
Location: Pennsylvania

iTrader: (0)

Quote:
Originally Posted by F87source View Post
Interesting, ive heard of the new bed plate design for the S55 awhile back but I don't recall the year.

Btw where do you get TSB info from?
I installed remote access onto my dealer's computer while he was in the bathroom...

jk, I get theom from here. http://www.carproblemzoo.com/tsb/bmw/m2/
Appreciate 2
      01-10-2020, 04:46 PM   #9
Anthony1s
Banned
756
Rep
2,149
Posts

Drives: 2018 Mineral Grey M2
Join Date: Oct 2017
Location: Pennsylvania

iTrader: (0)

Quote:
Originally Posted by F87source View Post
Interesting, ive heard of the new bed plate design for the S55 awhile back but I don't recall the year.

Btw where do you get TSB info from?
I was speaking with my service advisor today and he said that TSB only says to use loctite on the bedplate bolts. I used to be able to read the TSB repair procedures myself, so not sure if that website changed or if I was reading them on a different website. But there isn't a redesigned bedplate for us like the S55 had. Also was asking if I could get that TSB done as preventative maintenance and if TSB's were covered outside of warranty. Here's what he said.

Appreciate 1
      01-10-2020, 05:18 PM   #10
F87source
Major General
F87source's Avatar
No_Country
7178
Rep
7,343
Posts

Drives: Bmw M2
Join Date: Aug 2018
Location: .

iTrader: (1)

Quote:
Originally Posted by Anthony1s View Post
I was speaking with my service advisor today and he said that TSB only says to use loctite on the bedplate bolts. I used to be able to read the TSB repair procedures myself, so not sure if that website changed or if I was reading them on a different website. But there isn't a redesigned bedplate for us like the S55 had. Also was asking if I could get that TSB done as preventative maintenance and if TSB's were covered outside of warranty. Here's what he said.

Interesting, thanks for the info.

I wonder how much work it would take to diy it.
__________________
Click on the link below to see a compiled list of every review I have ever written:
https://f87.bimmerpost.com/forums/sh...2#post30368242
Appreciate 0
Post Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -5. The time now is 02:52 AM.




m2
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST