Change the differential
#1
Thread Starter
Senior Members
Joined: Sep 2005
Posts: 4,096
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From: Italy, Milano
My Ride: 545i SMG with Limited Slip Differential
Model Year: 2005
Hi guys!
In prevoius months here we talked a lot about an important mod : modify the final drive ratio to have shorter gears on 545i/550i .
Has someone done this ?
I have found the diff I would like and it is the diff of manual/SMG 530i .
( http://www.realoem.com/bmw/showparts.do?mo...hg=33&fg=05 )
I would like to do the mod, but the part (new differential) costs about $1500 ... But I'm not sure that it could work .. And $1500 to dissipate are too, if it will not work .
Idea :
How many members have 545i/550i SMG ?
$100 for everyone and one of they could try to do this mod .
$100 is the price of a fuel of gas ...
There are another possibility : www.bimmerworld.com sells also the part for 3.23 final drive ratio, at $595 (less for a group buy) .
But it is not an original BMW part .
Your opinions ?
It would be a great mod, if doable ...
In prevoius months here we talked a lot about an important mod : modify the final drive ratio to have shorter gears on 545i/550i .
Has someone done this ?
I have found the diff I would like and it is the diff of manual/SMG 530i .
( http://www.realoem.com/bmw/showparts.do?mo...hg=33&fg=05 )
I would like to do the mod, but the part (new differential) costs about $1500 ... But I'm not sure that it could work .. And $1500 to dissipate are too, if it will not work .
Idea :
How many members have 545i/550i SMG ?
$100 for everyone and one of they could try to do this mod .
$100 is the price of a fuel of gas ...
There are another possibility : www.bimmerworld.com sells also the part for 3.23 final drive ratio, at $595 (less for a group buy) .
But it is not an original BMW part .
Your opinions ?
It would be a great mod, if doable ...
#3
Members
Joined: Feb 2005
Posts: 215
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From: London, UK
My Ride: 2005 BMW-Alpina B5 Touring #007, Malachite Green w/ Caramel Individual interior
1999 BMW 840Ci Sport Individual, Techno Violet w/ Champagne Individual interior
I would worry slightly about whether it could take the torque of the 4.8 engine. At the very least, you'd want to make sure it had uprated cooling arrangements.
Other alternative is the diff from the 745d/Alpinas, but you're probably looking at even longer gearing - the B5 is geared for 200+mph!
Other alternative is the diff from the 745d/Alpinas, but you're probably looking at even longer gearing - the B5 is geared for 200+mph!
#4
Thread Starter
Senior Members
Joined: Sep 2005
Posts: 4,096
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From: Italy, Milano
My Ride: 545i SMG with Limited Slip Differential
Model Year: 2005
Originally Posted by hythe' post='339139' date='Sep 27 2006, 12:22 PM
I would worry slightly about whether it could take the torque of the 4.8 engine. At the very least, you'd want to make sure it had uprated cooling arrangements.
Other alternative is the diff from the 745d/Alpinas, but you're probably looking at even longer gearing - the B5 is geared for 200+mph!
Other alternative is the diff from the 745d/Alpinas, but you're probably looking at even longer gearing - the B5 is geared for 200+mph!
Keep at mind that 645ci has 3.45 final drive ratio and IMHO all 5er differentials are equal except the ratio .
#5
Members
Joined: Feb 2005
Posts: 215
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From: London, UK
My Ride: 2005 BMW-Alpina B5 Touring #007, Malachite Green w/ Caramel Individual interior
1999 BMW 840Ci Sport Individual, Techno Violet w/ Champagne Individual interior
Originally Posted by AlexFW' post='339178' date='Sep 27 2006, 03:18 PM
Keep at mind that 645ci has 3.45 final drive ratio and IMHO all 5er differentials are equal except the ratio .
They really ought to have used the tougher Alpina/745d diff for the 535d, though - doesn't take too much for one of those to be putting out 700Nm, which is beyond the rating of the standard diff.
#6
Thread Starter
Senior Members
Joined: Sep 2005
Posts: 4,096
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From: Italy, Milano
My Ride: 545i SMG with Limited Slip Differential
Model Year: 2005
Originally Posted by hythe' post='339179' date='Sep 27 2006, 04:20 PM
All except the M5 and B5, at least...
Eh, ok, thus the 530i diff is the same of 545i diff but with different final drive ratio .
Right ?
Who has spoken of B5 ?
#7
Members
Joined: Feb 2005
Posts: 215
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From: London, UK
My Ride: 2005 BMW-Alpina B5 Touring #007, Malachite Green w/ Caramel Individual interior
1999 BMW 840Ci Sport Individual, Techno Violet w/ Champagne Individual interior
Originally Posted by AlexFW' post='339209' date='Sep 27 2006, 04:47 PM
Who has spoken of B5 ?
But anyway, your point about 530 vs. 545 is valid.
Can't believe the standard 520i diff is up to the task of 600+Nm, but I'm sure you're right.
#8
Contributors
Joined: Apr 2005
Posts: 7,363
Likes: 1
From: San Diego, CA
My Ride: 2007 E63 AMG | Obsidian Black | Schwarzes Nappa | Black BirdEye Maple | Premium II Package | Electronic Trunk Closer | Parktronic
Engine: RPi/Powerchips custom ECU tune, RPi Ram Air Kit (BMC filter, scoops), RennTech Sport exhaust, secondary cats, charcoal and resonator delete, custom AAA x-pipe
Exterior: 50% side windows / 35% rear window Formula One Pinnacle Series | Flat AMG hood emblem
Suspension: Renntech Lowering Module
Wheels/Tires: Radenergie R10, Falken FK452 245/30/20, Yokohama ADVAN Sport 285/25/20
-----------------------------------------
2005 545i Sport SMG | Ti Grau | Schwarzes Dakota | Anthracite Maple | Logic 7 | Nav
Engine: Custom AFE CAI, Superchips ECU remap, Sprint Booster, RDSport Dual Exhaust Conversion with Quad Pipes and X-pipe, 3 resonators deleted, 90mm tips!
Exterior: M-Tech Aero kit | M5 Mirrors | M5 Rear Bumper | Trunk Lid Finisher | Vorsteiner decklid spoiler | 50% Formula One Pinnacle Tint
Suspension and Brakes: Bilstein PSS9 coilovers, JBT BBK: 16" cross-drilled rotors, 8 piston and 15" cross-drilled rotors, 4 piston
Wheels: VIP Modular VR 02 20x9F, 20x10R | Toyo T1R 245/30/20F, 285/25/20R
Lights: PIAA 4150K Xtreme White Plus fog lights, AIB v3
MOST IMPORTANT: Hardwired V1; =)
ED Date: 4/7/05, Re-delivery date: 5/21/05
Alex,
The best and surest way proceed with the differential swap would be to get one from a 545 Step.
The best and surest way proceed with the differential swap would be to get one from a 545 Step.
#9
Thread Starter
Senior Members
Joined: Sep 2005
Posts: 4,096
Likes: 0
From: Italy, Milano
My Ride: 545i SMG with Limited Slip Differential
Model Year: 2005
Originally Posted by vegastrashed' post='339283' date='Sep 27 2006, 08:48 PM
Alex,
The best and surest way proceed with the differential swap would be to get one from a 545 Step.
The best and surest way proceed with the differential swap would be to get one from a 545 Step.
#10
Contributors
Joined: Apr 2005
Posts: 7,363
Likes: 1
From: San Diego, CA
My Ride: 2007 E63 AMG | Obsidian Black | Schwarzes Nappa | Black BirdEye Maple | Premium II Package | Electronic Trunk Closer | Parktronic
Engine: RPi/Powerchips custom ECU tune, RPi Ram Air Kit (BMC filter, scoops), RennTech Sport exhaust, secondary cats, charcoal and resonator delete, custom AAA x-pipe
Exterior: 50% side windows / 35% rear window Formula One Pinnacle Series | Flat AMG hood emblem
Suspension: Renntech Lowering Module
Wheels/Tires: Radenergie R10, Falken FK452 245/30/20, Yokohama ADVAN Sport 285/25/20
-----------------------------------------
2005 545i Sport SMG | Ti Grau | Schwarzes Dakota | Anthracite Maple | Logic 7 | Nav
Engine: Custom AFE CAI, Superchips ECU remap, Sprint Booster, RDSport Dual Exhaust Conversion with Quad Pipes and X-pipe, 3 resonators deleted, 90mm tips!
Exterior: M-Tech Aero kit | M5 Mirrors | M5 Rear Bumper | Trunk Lid Finisher | Vorsteiner decklid spoiler | 50% Formula One Pinnacle Tint
Suspension and Brakes: Bilstein PSS9 coilovers, JBT BBK: 16" cross-drilled rotors, 8 piston and 15" cross-drilled rotors, 4 piston
Wheels: VIP Modular VR 02 20x9F, 20x10R | Toyo T1R 245/30/20F, 285/25/20R
Lights: PIAA 4150K Xtreme White Plus fog lights, AIB v3
MOST IMPORTANT: Hardwired V1; =)
ED Date: 4/7/05, Re-delivery date: 5/21/05
Alright, I'm just going to sit back and wait for you to complete this mod. Hope everything works out!