E61 Body Rigidity
#31
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Ok I found something - thanks to Gustav @ M5Board.com and the video he posted of his Supersprint installation in Italy!
You can see the whole video here: video
Please pay particular attention to the footage between minutes 10:00 and 12:35.
Here is one screenshot where we can see the basic layout. My comments:
1. The two large braces #7 are clearly visible, although I must say they look much larger than on my 530d Touring! Also a bit earlier in the video, one (or both) of these braces is specifically manufactured at the install shop. Therefore, I guess these may be custom braces that replace the original #7s? Or one of them is stock (i.e. its #18 and #21), and the other is custom made.
2. Both braces #14 are clearly visibile as well. I will have to look under my car to see whether I have them.
Attachment 116763
Great video well done! I definitely do not have braces #14 on mine, I would agree with you that they replaced the #7 braces with custom manufactured sets at the shop to fit the new exhaust they really look beefy... Hard to find where #18 and #21 are. Also I noticed that the front subframe had a very significant brace (large aluminum piece) that covered the entire area between the front wheels - that must be specific to the M5 but it looked very substantial (I have not removed my underbody cover over that area to see what I have on my car. I have the XIT model in the States, sadly they never sold the M5 Touring here. The question is can we fit those other braces (#14, #18??, #21??) to our models. If the dealers sold the M5 Touring I would ask the service tech if it would be possible, but I guess that question needs to come from someone in Europe.
Ultra racing makes braces but they will not fit the X models (at least in the front- different subframe) perhaps the other bars for the rear would work as well. They also just came out with a strut tower brace for the E60 (fits 530) again not sure it clears the 535 N54 engine or not.
You can see the whole video here: video
Please pay particular attention to the footage between minutes 10:00 and 12:35.
Here is one screenshot where we can see the basic layout. My comments:
1. The two large braces #7 are clearly visible, although I must say they look much larger than on my 530d Touring! Also a bit earlier in the video, one (or both) of these braces is specifically manufactured at the install shop. Therefore, I guess these may be custom braces that replace the original #7s? Or one of them is stock (i.e. its #18 and #21), and the other is custom made.
2. Both braces #14 are clearly visibile as well. I will have to look under my car to see whether I have them.
Attachment 116763
Great video well done! I definitely do not have braces #14 on mine, I would agree with you that they replaced the #7 braces with custom manufactured sets at the shop to fit the new exhaust they really look beefy... Hard to find where #18 and #21 are. Also I noticed that the front subframe had a very significant brace (large aluminum piece) that covered the entire area between the front wheels - that must be specific to the M5 but it looked very substantial (I have not removed my underbody cover over that area to see what I have on my car. I have the XIT model in the States, sadly they never sold the M5 Touring here. The question is can we fit those other braces (#14, #18??, #21??) to our models. If the dealers sold the M5 Touring I would ask the service tech if it would be possible, but I guess that question needs to come from someone in Europe.
Ultra racing makes braces but they will not fit the X models (at least in the front- different subframe) perhaps the other bars for the rear would work as well. They also just came out with a strut tower brace for the E60 (fits 530) again not sure it clears the 535 N54 engine or not.
#32
Also I noticed that the front subframe had a very significant brace (large aluminum piece) that covered the entire area between the front wheels - that must be specific to the M5 but it looked very substantial (I have not removed my underbody cover over that area to see what I have on my car. I have the XIT model in the States, sadly they never sold the M5 Touring here. The question is can we fit those other braces (#14, #18??, #21??) to our models. If the dealers sold the M5 Touring I would ask the service tech if it would be possible, but I guess that question needs to come from someone in Europe.
Next time I bring the car to my mechanic, we will check together whether there are holes to attach #14, and space to get beefier #7s.
If the chassis is prepared for this, then its a question of trial and error. I would be keen to try it, unless the cost is prohibitive. Oddly enough, in RealOEM there are no prices for #14, #18 and #21..
Ultra racing makes braces but they will not fit the X models (at least in the front- different subframe) perhaps the other bars for the rear would work as well. They also just came out with a strut tower brace for the E60 (fits 530) again not sure it clears the 535 N54 engine or not.
- UR bars stiffen up the suspension frames, i.e. the suspension reaction will feel tighter when going over bumps.
- And the reinforcements stiffen up the body of the car, i.e. the body will not twist as much when going over bumps.
Those are two different things.
The strut brace is a very good point - it counts to the latter type, as it stiffens the body upfront. I have one and the effect is very noticeable. Mine cost around $160 and it looks really good as its made out of real carbon and aluminum, and the joints are effectively ACS replicas.
How much is that UR strut brace?
#33
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Good point on all the above. The #14 braces look like they attach to the subframe in the rear (rear axle mounting points - much like the rear UR braces do). It appears from REALOEM that the M5 has a unique real axle so the mounting points might be different from our cars as well. The UR strut brace was listed on ebay motors for around $140.00 USD. Claims it fits 530 models. I noticed other braces as well that look much like the one you have (sans CF but all aluminum). The UR is made of steel, I'm tempted to get it.
#34
I hope it turns out you're not right on that #14/rear axle observation..
On the UR strut brace, my observations:
+ It has two attachment points on each tower, which makes the whole construction more solid
+ It is a one-piece design which should theoretically eliminate any twist
- It has no joints that allow the middle piece to be taken out quickly when doing work on the engine.
- You should ask whether it fits the 535i. It seems that bars of similar design don't fit the 535.
(- Its very ugly, and it won't integrate well visually in the engine compartment, but you can still at least paint it black)
That's mine (excuse the dirty engine bay, it was properly detailed soon after):
On the UR strut brace, my observations:
+ It has two attachment points on each tower, which makes the whole construction more solid
+ It is a one-piece design which should theoretically eliminate any twist
- It has no joints that allow the middle piece to be taken out quickly when doing work on the engine.
- You should ask whether it fits the 535i. It seems that bars of similar design don't fit the 535.
(- Its very ugly, and it won't integrate well visually in the engine compartment, but you can still at least paint it black)
That's mine (excuse the dirty engine bay, it was properly detailed soon after):
#35
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Thanks for the great pics. I can't seem to find that particular bar it looks very high quality and well sorted out. I agree on the look of the UR bar, not very attractive, my car color is black sapphire what a contrast... Keep us in the loop if you are able to sort out the questions we both have on the additional braces (#14, etc). I think the contributions by everyone writing in response to this original posting about "body rigidity" have been extremely informative. Thanks for the updates everyone!
#36
I'll just say THANK YOU RICKY he has tested it for us
https://5series.net/forums/topic/112...4#entry1337484
https://5series.net/forums/topic/112...4#entry1337484
#37
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WOW!! Great post thanks for sharing. The braces look very substantial. I wonder if they will clear our other factory braces? - Thinking about it, these would have to mount on top of the current "V" brace we have on our E61 as they would intersect at some point (probably in the middle). I guess with some spacers it would work. I really want to get a pair and try this. If we can combine our existing "V" brace with these bars and also add the third (last) Ultra Racing bar I would think we would have a very solid back structure.
I'll just say THANK YOU RICKY he has tested it for us
https://5series.net/forums/topic/112...4#entry1337484
https://5series.net/forums/topic/112...4#entry1337484
#38
The E61 M5 has both the V-brace and these pull-rods, so clearing is not a problem
If you look on the previous page, you can see them all on the video screenshot.
Ideally there should be a way to fit a middle UR bar as well, but you can't have everything in life.. Besides, I think the pull rods and the UR bar serve fundamentally different purposes. The pull rods are against chassis flex, whereas the UR bar eliminates movements within the suspension subframe and presumably has almost zero effect on body flex.
If you look on the previous page, you can see them all on the video screenshot.
Ideally there should be a way to fit a middle UR bar as well, but you can't have everything in life.. Besides, I think the pull rods and the UR bar serve fundamentally different purposes. The pull rods are against chassis flex, whereas the UR bar eliminates movements within the suspension subframe and presumably has almost zero effect on body flex.
#39
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The E61 M5 has both the V-brace and these pull-rods, so clearing is not a problem
If you look on the previous page, you can see them all on the video screenshot.
Ideally there should be a way to fit a middle UR bar as well, but you can't have everything in life.. Besides, I think the pull rods and the UR bar serve fundamentally different purposes. The pull rods are against chassis flex, whereas the UR bar eliminates movements within the suspension subframe and presumably has almost zero effect on body flex.
If you look on the previous page, you can see them all on the video screenshot.
Ideally there should be a way to fit a middle UR bar as well, but you can't have everything in life.. Besides, I think the pull rods and the UR bar serve fundamentally different purposes. The pull rods are against chassis flex, whereas the UR bar eliminates movements within the suspension subframe and presumably has almost zero effect on body flex.
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My Ride: BMW 535xi wagon. Monaco Blue/Dakota Brown interior, M Package
guys,
I'm talking to Evan at nextgentuning which is the US distributor for the UR bars. I have linked this post to my email so he can see what we are all talking about. The more i drive the car and experience stuff like the steering wheel shuddering over bumps (like a 1970's american convertible) I am more and more shocked by how horrible the chassis flex is. Something HAS to be done... hopefully if we can find a
-front strut bar (if i can find one for the 535!... none yet.. let me know if you know of one please)
-front UR bar:
-M5 bars like on this post (still don't see how these fit OVER our diagonal bars though)
-rear UR bar (asking Evan about this also)
we can come close to fixing this problem... I'm tired of my windows rattling inside their seats when i go over minor potholes@
I'm talking to Evan at nextgentuning which is the US distributor for the UR bars. I have linked this post to my email so he can see what we are all talking about. The more i drive the car and experience stuff like the steering wheel shuddering over bumps (like a 1970's american convertible) I am more and more shocked by how horrible the chassis flex is. Something HAS to be done... hopefully if we can find a
-front strut bar (if i can find one for the 535!... none yet.. let me know if you know of one please)
-front UR bar:
-M5 bars like on this post (still don't see how these fit OVER our diagonal bars though)
-rear UR bar (asking Evan about this also)
we can come close to fixing this problem... I'm tired of my windows rattling inside their seats when i go over minor potholes@