Front sway bar swap

Used2be · 02-13-2014, 12:43 PM

I'm changing the stock front sway bar to the CP sway bar. BMW has built their bars in a way I haven't seen before. They have a reduced diameter in the middle of the bar, and then thicker out to the ends. The primary difference from the stock bar to the CP bar is the length of that reduced diameter. On the stock bar it is 16.312 " between the masking tape markers, and on the CP bar it is 8". The diameter of the bar as it thickens through the mount and out to the ends is 1.150" with some variation in the twists and turns. There was a slight diameter difference in the reduced diameter portion of the bars. The CP bar was .031" thicker at 1.031" to the stock diameter of exactly 1". I'm showing you the bodywork removal needed to take out the headlights. I'm going to paint those with a slightly darker tint for some contrast and am hoping I will like it. It's not difficult to remove all that stuff, just time consuming.

Driving update: Finally able to drive with some zest and see how the new bars affect handling on public roads. Left the suspension setting in comfort to better feel the sway bar contribution as the car corners. Turn in is much better feeling than with the standard bar, less body lean and a tauter, more direct feel and the car stays planted. Over an uneven road surface with undulations on either side of the car, not potholes, the ride is a little more harsh. The car does tip from side to side more with the stiffer bar, which I happen to like, others may not.

RPiM5 · 02-13-2014, 01:12 PM

Dude! Wow, thanks for posting this! Just one question. How did you order the CP Sway bar?? Did you also get the CP bushings and springs?? Thanks!

Oh and how much did they charge you for the Sway bar??

Used2be · 02-13-2014, 02:04 PM

Quote:

Originally Posted by RPiM5

Oh and how much did they charge you for the Sway bar??

Ordered from the dealer I bought the car from, part #31-35-7-850-119. Did not get the bushings, and I'm still debating on springs. Might do a coil-over, but would rather find a stiffer spring that will mount on the standard strut. That could be the CP spring, but I'd love to find out if BMW just buys the H&R spring and doubles the cost?

I paid full retail I believe for the CP sway bar, $311.18. I'm attaching the retail costs quoted to me from the dealer for the front and rear CP springs, struts, and bump stops for the CP struts which are called absorbers on this quote.

RPiM5 · 02-13-2014, 08:41 PM

Quote:

Originally Posted by Used2be

Ordered from the dealer I bought the car from, part #31-35-7-850-119. Did not get the bushings, and I'm still debating on springs. Might do a coil-over, but would rather find a stiffer spring that will mount on the standard strut. That could be the CP spring, but I'd love to find out if BMW just buys the H&R spring and doubles the cost?

I paid full retail I believe for the CP sway bar, $311.18. I'm attaching the retail costs quoted to me from the dealer for the front and rear CP springs, struts, and bump stops for the CP struts which are called absorbers on this quote.

Sweet! Thanks for all of this great info. A while back I tried to get this info from my dealer and they said it wasn't available yet and I just kind of forgot about it. So I'm guessing the absorbers are the bushings then? $300 bucks doesn't seem bad at for CP sway bars. It's about the same price I paid for aftermarket sway bars on my E60 M5. Nicely done!

Also here's a thought. I wonder if the Front and Rear struts are different for the Comp Pack than they are for the non Comp Pack. And I wonder if you tried to put the Comp Pack Springs on an M5 with non-Comp Pack Struts, what that would mean, assuming that the struts are in fact different. As far as I know, know one has yet tried to put Comp Pack Springs on a Pre-LCI M5. Hmmm...

Used2be · 02-14-2014, 07:21 AM

Quote:

Originally Posted by RPiM5

I wonder if the Front and Rear struts are different for the Comp Pack than they are for the non Comp Pack. And I wonder if you tried to put the Comp Pack Springs on an M5 with non-Comp Pack Struts, what that would mean, assuming that the struts are in fact different. As far as I know, know one has yet tried to put Comp Pack Springs on a Pre-LCI M5. Hmmm...

I've considered that also and my guess is that the CP struts will be different only in the internals, and that the spring perch position is identical. If the spring mounting position on the CP strut were different I'd think that'd make the CP springs unusable for the non-CP struts.

The absorbers are the bump stop cushioning pads that go on the shock rod to help with a severe compression event. Probably more dense material and slightly different dimension from the non CP version.

DrKevM5 · 02-14-2014, 03:11 PM

I'm curious why you aren't also going with the rear CP swaybar also?

stealth.pilot · 02-14-2014, 04:22 PM

Quote:

Originally Posted by RPiM5

Sweet! Thanks for all of this great info. A while back I tried to get this info from my dealer and they said it wasn't available yet and I just kind of forgot about it. So I'm guessing the absorbers are the bushings then? $300 bucks doesn't seem bad at for CP sway bars. It's about the same price I paid for aftermarket sway bars on my E60 M5. Nicely done!

Also here's a thought. I wonder if the Front and Rear struts are different for the Comp Pack than they are for the non Comp Pack. And I wonder if you tried to put the Comp Pack Springs on an M5 with non-Comp Pack Struts, what that would mean, assuming that the struts are in fact different. As far as I know, know one has yet tried to put Comp Pack Springs on a Pre-LCI M5. Hmmm...

IND quoted me 500 something for front and rear. That is the way to go if you're doing it.

DrKevM5 · 02-14-2014, 05:22 PM

I assume your referring to the sways, Stealth? Anyone have a part number for the rear?

Used2be · 02-14-2014, 05:33 PM

Quote:

Originally Posted by DrKevM5

I'm curious why you aren't also going with the rear CP swaybar also?

I made my judgement for the bar purchase on information I got from Ilia at IND. I had asked him to measure the CP bars they had in stock so I could compare that to the dimensions I had from my stock bars. He gave me a 29mm diameter measurement for the front bar, which was larger than the 25mm I had for the stock bar, so I was confident that was a stiffer bar than stock. He gave me the rear bar diameter as 21mm which is the same as my stock bar. Now, after having the CP front bar I believe that Ilia took his dimension measurement on the thicker portion of the bar, not the center, for the front. Perhaps he took his measurement of the rear bar in the center, where it is still the 21mm diameter, but didn't observe the reduced distance of that dimension in the rear bar. The stock rear bar does change diameter at the mounting point to .900", so perhaps, as the front bar does, that 21mm dimension length is reduced in length also? I may purchase the rear bar just on the hope that BMW also changed its construction.

The retail price I was given for the rear bar from my dealer was $237.96, part #33 55 7 850 120.

DrKevM5 · 02-14-2014, 05:38 PM

Good info. Thanks! I think I'll do both.

runningthingz · 03-03-2014, 10:41 AM

Has anyone done the Dinan anti roll bars?

http://dinancars.com/product/d120-05...ries&mid=1163/

http://dinancars.com/product/d120-05...ries&mid=1163/

rwassily · 11-16-2016, 12:10 PM

If anyone is interested in selling his M5 front sway bar, please let me know; I am looking to install one on my 535xi; it's expensive here in Canada as everything else.
If you prefer not to ship to Canada, I will provide a US address.

02-13-2014, 12:43 PM	#1
Used2be Perennial PFC 336 Rep 1,274 Posts Drives: F90 M5 DG/Aragon Join Date: Oct 2012 Location: Michigan, USA iTrader: (0)	Front sway bar swap I'm changing the stock front sway bar to the CP sway bar. BMW has built their bars in a way I haven't seen before. They have a reduced diameter in the middle of the bar, and then thicker out to the ends. The primary difference from the stock bar to the CP bar is the length of that reduced diameter. On the stock bar it is 16.312 " between the masking tape markers, and on the CP bar it is 8". The diameter of the bar as it thickens through the mount and out to the ends is 1.150" with some variation in the twists and turns. There was a slight diameter difference in the reduced diameter portion of the bars. The CP bar was .031" thicker at 1.031" to the stock diameter of exactly 1". I'm showing you the bodywork removal needed to take out the headlights. I'm going to paint those with a slightly darker tint for some contrast and am hoping I will like it. It's not difficult to remove all that stuff, just time consuming. Driving update: Finally able to drive with some zest and see how the new bars affect handling on public roads. Left the suspension setting in comfort to better feel the sway bar contribution as the car corners. Turn in is much better feeling than with the standard bar, less body lean and a tauter, more direct feel and the car stays planted. Over an uneven road surface with undulations on either side of the car, not potholes, the ride is a little more harsh. The car does tip from side to side more with the stiffer bar, which I happen to like, others may not. Attached Images Last edited by Used2be; 03-31-2014 at 09:57 AM.. Reason: Posted update
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02-13-2014, 01:12 PM	#2
RPiM5 Major General 2873 Rep 7,885 Posts Drives: Black M5 Join Date: Apr 2012 Location: Earth 616 iTrader: (0)	Dude! Wow, thanks for posting this! Just one question. How did you order the CP Sway bar?? Did you also get the CP bushings and springs?? Thanks! Oh and how much did they charge you for the Sway bar?? __________________
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02-14-2014, 03:11 PM	#6
DrKevM5 Colonel 2274 Rep 2,523 Posts Drives: G05 X5, F87 M2 Join Date: Aug 2008 Location: Western NY iTrader: (7)	I'm curious why you aren't also going with the rear CP swaybar also? __________________ ?16 M2 Long Beach Blue/Black, 6MT '22 X5 4.0 M Sport Black Sapphire/Tartufo ?22 Tesla Model Y Performance Midnight Silver/White
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02-14-2014, 05:22 PM	#8
DrKevM5 Colonel 2274 Rep 2,523 Posts Drives: G05 X5, F87 M2 Join Date: Aug 2008 Location: Western NY iTrader: (7)	I assume your referring to the sways, Stealth? Anyone have a part number for the rear? __________________ ?16 M2 Long Beach Blue/Black, 6MT '22 X5 4.0 M Sport Black Sapphire/Tartufo ?22 Tesla Model Y Performance Midnight Silver/White
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02-14-2014, 05:38 PM	#10
DrKevM5 Colonel 2274 Rep 2,523 Posts Drives: G05 X5, F87 M2 Join Date: Aug 2008 Location: Western NY iTrader: (7)	Good info. Thanks! I think I'll do both. __________________ ?16 M2 Long Beach Blue/Black, 6MT '22 X5 4.0 M Sport Black Sapphire/Tartufo ?22 Tesla Model Y Performance Midnight Silver/White
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03-03-2014, 10:41 AM	#11
runningthingz Second Lieutenant 20 Rep 273 Posts Drives: Frozen White M5 Join Date: Dec 2012 Location: San Diego, CA iTrader: (0)	Has anyone done the Dinan anti roll bars? http://dinancars.com/product/d120-05...ries&mid=1163/ http://dinancars.com/product/d120-05...ries&mid=1163/
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11-16-2016, 12:10 PM	#12
rwassily New Member 0 Rep 20 Posts Drives: E34 M5 // F10 535xi Join Date: May 2010 Location: montreal, qc, canada iTrader: (0)	If anyone is interested in selling his M5 front sway bar, please let me know; I am looking to install one on my 535xi; it's expensive here in Canada as everything else. If you prefer not to ship to Canada, I will provide a US address.
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