theALPINAregister.com Forum Index theALPINAregister.com
The Forum section of www.theALPINAregister.com
 
 FAQFAQ   SearchSearch   Site SearchSite Search   Forum SearchForum Search   MemberlistMemberlist   UsergroupsUsergroups  GalleryGallery   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

B3 3,3 differential options?

 
Post new topic   Reply to topic    theALPINAregister.com Forum Index -> ALPINA - Car Advice / Information
View previous topic :: View next topic  
Author Message
lanab



Joined: 05 Jul 2013
Posts: 27

PostPosted: Mon Oct 15, 2018 10:02 pm    Post subject: B3 3,3 differential options? Reply with quote

What alternatives are there to change the differential on the B3 3.3?

The gear ratio is 3,64 and Type 188 according to the Alpina parts manual, but i can't find any differentials available to buy used or refurbished? any recommendations? only option buying a new one or refurbish the one i have?
_________________
BMW Alpina B3 3.3 -01
BMW F10 M5
Back to top
View user's profile Send private message
ali
ALPINA
ALPINA


Joined: 10 Feb 2007
Posts: 1956
Location: Edinburgh

PostPosted: Mon Oct 15, 2018 10:52 pm    Post subject: Reply with quote

The diff should just be a standard 330i item.
It isn't Alpina specific so should be able to get hold of one from a decent breakers yard like Quarry motors or Fab Direct
_________________
B3 3.3 Touring #108
B10 V8 #540
B3 3.0 Biturbo #107
E46 M3 Convertible
Back to top
View user's profile Send private message
lanab



Joined: 05 Jul 2013
Posts: 27

PostPosted: Mon Oct 15, 2018 11:15 pm    Post subject: Reply with quote

Problem is that the standard diff on the 328/330 have a ratio of 3,46 and i need 3,64
_________________
BMW Alpina B3 3.3 -01
BMW F10 M5
Back to top
View user's profile Send private message
ali
ALPINA
ALPINA


Joined: 10 Feb 2007
Posts: 1956
Location: Edinburgh

PostPosted: Tue Oct 16, 2018 9:42 am    Post subject: Reply with quote

330i Auto that the B3 3.3 is based on is 3.64
E85 X3 3.0i manual also used same diff
See here


_________________
B3 3.3 Touring #108
B10 V8 #540
B3 3.0 Biturbo #107
E46 M3 Convertible
Back to top
View user's profile Send private message
lanab



Joined: 05 Jul 2013
Posts: 27

PostPosted: Tue Oct 16, 2018 12:50 pm    Post subject: Reply with quote

Thanks Very Happy
_________________
BMW Alpina B3 3.3 -01
BMW F10 M5
Back to top
View user's profile Send private message
lanab



Joined: 05 Jul 2013
Posts: 27

PostPosted: Thu Nov 08, 2018 8:35 pm    Post subject: Reply with quote

This is a problem now after trying to source a used one, the diff used by the B3 got a final ratio of 3,64 for the Swítchtronic model.

BMW never used any E46s in Europe with that final ratio, only in the U.S for both 328 and 330i used that diff.

I could change it to another ratio, but i don't know if that would be bad for driving and how much it will impact, would a final ratio of 3.07 be bad?

I tried with different gear ratio calculators to get an idea of it...... Crying or Very sad
_________________
BMW Alpina B3 3.3 -01
BMW F10 M5
Back to top
View user's profile Send private message
Ikule
ALPINA
ALPINA


Joined: 24 Sep 2007
Posts: 1993
Location: South Manchester

PostPosted: Thu Nov 08, 2018 10:31 pm    Post subject: Reply with quote

If your standard ratio is 3.64 then going to a 3.07 will harm the acceleration, as you are effectively raising the gearing,
it would cruise quietly on the motorway and the fuel economy would improve as the engine will be turning a lot slower at say 70 mph than it would with your current diff,
but when you try and accelerate it would feel quite a bit slower, even going to the nearest size of 3.46 would be a retrograde step in my opinion and would not give you the performance a B3 should have.

I've gone from the standard 2.93 in my B10 3.2 to a much friskier 3.15 ratio, it revs a few hundred rpm's higher at 70 on the motorway but the acceleration has improved quite nicely and I definitely wouldn't go back to the 2.93 diff.

You don't say whats wrong with your diff, I assume it's starting to whine in which case, due to a lack of used one's available (I just had a look on e-bay) I reckon a rebuild would be the best option,
maybe consider an upgrade at the same time and get Birds to fit a Quaife LSD, although the current price for the B3 3.3 at £1,670 inc vat (fitted) may count against this option.

http://www.birdsauto.com/quaife/search?m=bmw&s=42656&mi=Alpina+B3+3.3

Hope that helps (a bit!).
_________________
Steve C



'98 B10 3.2 #88 (for summer cruising)
'04 Mini Cooper S (commuting/sacrificial shopping trolley target....)
'94 325i Coupe SOLD
'88 Vauxhall Senator 3.0i SOLD
'90 Astra MkII GTE 16V (Turbo conversion) SOLD
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    theALPINAregister.com Forum Index -> ALPINA - Car Advice / Information All times are GMT + 2 Hours
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group