Bilstein B12 difference between conv & coupe

Chris N · 06-24-2018, 07:10 AM

Curious what difference is between the B12 kits for the 128i coupe (46-180537) vs the convertible (46-180520)? Some of the of the various website configuration tools list the 46-180537 for both applications.

Also, is there really a difference between the manufacture dates before or after 9/10? This came up a couple of times as I have been sourcing parts.

desertman123 · 06-26-2018, 08:59 AM

Lmao we are literally wondering the same thing. I figured it's heavier springs to cope with the heavier car.

I ordered the convertible ones by accident and I'm just gonna send it. I think I got some of the last ones TireRack had in stock.

gjm120 · 06-26-2018, 11:11 AM

There was a supposed change in the rear springs from progressive to linear 2011. See this thread:
http://www.1addicts.com/forums/showthread.php?t=471267

I have a set of 08 135i rear springs and can't see a differece in coil spacing or thickness that would indicate progressive rates. Maybe it's just too subtle for me to see.

Chris N · 06-26-2018, 02:17 PM

Quote:

Originally Posted by desertman123

Lmao we are literally wondering the same thing. I figured it's heavier springs to cope with the heavier car.

I ordered the convertible ones by accident and I'm just gonna send it. I think I got some of the last ones TireRack had in stock.

Yeah.... I had my finger on the trigger but wasn't comfortable with not knowing the fitment.

128Styll · 07-04-2018, 09:37 PM

Was a suitable alternative ever discovered?

Chris N · 07-06-2018, 07:52 AM

Quote:

Originally Posted by 128Styll

Was a suitable alternative ever discovered?

I decided to wait. I'm unwilling to take the chance. I will probably just source the parts later.

06-24-2018, 07:10 AM	#1
Chris N Second Lieutenant 153 Rep 246 Posts Drives: BMW M2c Join Date: Sep 2016 Location: Cincinnati, OH iTrader: (0)	Bilstein B12 difference between conv & coupe Curious what difference is between the B12 kits for the 128i coupe (46-180537) vs the convertible (46-180520)? Some of the of the various website configuration tools list the 46-180537 for both applications. Also, is there really a difference between the manufacture dates before or after 9/10? This came up a couple of times as I have been sourcing parts. Last edited by Chris N; 06-25-2018 at 05:40 AM..
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06-26-2018, 08:59 AM	#2
desertman123 E82 Mudflap Ambassador 2214 Rep 2,219 Posts Drives: '08 128i Join Date: May 2016 Location: Orlando, FL iTrader: (0) Garage List 1992 Honda Beat [9.50] 2008 BMW 128i [10.00] 2014 BMW 528i [10.00]	Lmao we are literally wondering the same thing. I figured it's heavier springs to cope with the heavier car. I ordered the convertible ones by accident and I'm just gonna send it. I think I got some of the last ones TireRack had in stock. __________________ My 2008 128i - Sparkling Graphite/Beige - Sport pkg - 6MT - Click me! Parents' 2014 528i - Mineral White/Ivory White - fully loaded Instagram @Andreys_128i and @Honda.Bito
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06-26-2018, 11:11 AM	#3
gjm120 Colonel 2182 Rep 2,806 Posts Drives: 2013 128i, 2021 230i Join Date: Jan 2016 Location: East Texas iTrader: (1)	There was a supposed change in the rear springs from progressive to linear 2011. See this thread: http://www.1addicts.com/forums/showthread.php?t=471267 I have a set of 08 135i rear springs and can't see a differece in coil spacing or thickness that would indicate progressive rates. Maybe it's just too subtle for me to see. __________________ E82 / BMWP Springs / Koni Yellows / M front control arms / Adjustable front endlinks / M rear guide rods / Whiteline Poly RSFB
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07-04-2018, 09:37 PM	#5
128Styll Colosseum Chariot Driving Instructor 4 Rep 21 Posts Drives: Slow '12 128i Join Date: Jul 2018 Location: SoCal iTrader: (0)	Was a suitable alternative ever discovered?
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