Help with Suspension Refresh at 50k miles/10 years

[Vas]

Total amount spent out of curiosity?

[BMWCurves]

Total amount spent out of curiosity?

Let's see...

• Koni Sport (Yellows) struts (8741-1390RSPORT [front right], 8741-1390LSPORT [front left]) and shocks [2x 8040-1271SPORT]) - $498.64 (Race Consulting Agency)
• Rogue Engineering rear shock mounts (RSM) (no part number) - $99 (Rogue Engineering)
• Strut tower reinforcement plates (2x 51717036781) - $19.90 (TMS)
• Front strut mount (2x 31336752735) (FCP Euro) - $57.98 (FCP Euro)
• Front spring pads (Upper: 2x 31331091867, Lower: 2x 31331096664) - $19.80 (TMS)
• Rear spring pads (Upper: 2x 33531136385, Lower: 2x 33531094518) - $31.80 (TMS)
• Bump stops (Front: 2x 31306757046, Rear: 2x 33506757047) - $45.80 (TMS)
• Dust boots (Front: 2x 31331094749, Rear: 2x 33521136283) - $16.28 (TMS)
• Z4M Front Control Arm Bushing (FCAB) (Left: 31107836862, Right: 31107836863) - $143.98 (FCP Euro)
• Hex bolt w/ washer for FCABs (4x 33306760652) - $11.56 (FCP Euro)
• Locking nuts for strut mounts (6x 31316769731) - $5.70 (TMS)
• Shipping - $13.01 (Rogue Engineering) + $19.29 (TMS) (Race Consulting Agency and FCP Euro were free)

Grand total: $1,002.78

Quite pricey when you look at it. But that $1k should last me 50k miles on the very low side, and I'll have the peace of mind knowing that all those ancillary parts are new. Should you be looking for a more frugal option, you could definitely skip replacing a lot of those items.

[BMWCurves]

Bump with a new topic/question: RTABs and limiters

I've decided I might as well do my RTABs now. Since I want to keep a comfortable ride and heard that poly RTABs can increase NVH as well as other issues, I'm considering either the M3 or Z4M RTABs but don't know what to go with. Is there a difference between the two? I'm struggling to find any definitive answer one way or the other.

Since I'm doing RTABs it sounds like I should also get limiters. I saw Derbo uses Turner Motorsports' version, I was eyeing Vorshlag's set, and I saw there are a few other companies out there that do them.

Any suggestions/info on RTABs as well as a brand of limiters would be greatly appreciated!

[BMWCurves]

Update:

I have installed everything on my list from the first page except for the FCABs and RTABs (you can read about the install in my project thread here for the rear shocks and here for the front struts).

Notes:
I haven't gotten an alignment yet so I haven't really gone canyon carving and gotten a feel for its handling, improved or otherwise. However, I should say though that the comfort is much improved with the Konis over the original shocks and struts. I am still aware of bumps, but where they used to be jarring with the old units, they're now something I am merely conscious of and don't bother me. I set both the fronts and the rears to 3/4 turn from soft. I may adjust that in the future but for now they're great.

When I pulled out the old Sachs shocks and struts I did not notice any weeping of fluid, but they were definitely degraded. The rear shocks, when compressed, did not rebound at all. They took over 5 minutes to fully rebound. The front struts did have some rebound left in them, but still were very slow and clearly degraded. So I'm not sure if it was the miles (50k), the age (10 years), or a combination of the two, but they were due for replacement and I'm glad I went with the Konis.

I will update again when I have installed the FCABs and RTABs and gotten an alignment. I decided to go with both Z4M FCABs (Left: 31107836862, Right: 31107836863) and RTABs (33326770817 (2x)), as well as Vorshlag limiters since there didn't seem to be a whole lot of difference between their product and ones from Turner Motorsport and other vendors.

[BMWCurves]

Updated the first post with my thoughts after getting everything installed.

[NoVAphotog]

Updated the first post with my thoughts after getting everything installed.

Update on thoughts, tips, advice? Starting to build list based on yours to follow in your footsteps in the Spring.

[BMWCurves]

I absolutely love it. The car feels a lot tighter and more eager to turn into corners than it did before. The ride comfort has also improved. It's still stiff, but not spine-jarringly so. It just feels very connected with the road which is what I like. My father took a spin in the car a few days ago for the first time since I installed all these suspension parts and he commented that it felt much better. Really tight, planted, and agile. If you plan to keep your car for awhile I would change out all the parts I used but that is of course at your discretion. You certainly don't have to get new dust boots, bump stops, spring pads, etc. I just figured I might as well since I'm already in there and that way I won't have to change them out for another 10 years.

The only items I would consider changing would be the RTABs and the springs. I thought about the spherical RTABs that Slater is putting in his car but I opted to stick with the Z4M RTABs (with limiters), which work wonderfully so far. I briefly considered lowering springs for aesthetics and/or stiffer springs for performance, but I eventually opted to stay with the stock springs because I like the physical clearance (I would scrape on any sharp angled driveways) and the ride is plenty stiff for me. Plus I could save money and spend it elsewhere.

As for tips, if this is your first time installing shocks/struts and other parts, take your time, read up on it (the links in the first post of this thread can be helpful). I would especially suggest that you take a picture of the spring's orientation on the front struts before disassembling them. I made the mistake of not taking a picture and seating the spring improperly from memory and having to recompress the spring and orient it correctly, which was a pain and took a lot of time. If you have an air ratchet, you're a lucky son of a gun, it'll make the job a lot easier. Otherwise prepare for a bit of a workout.

Other things:

• The new strut mounts I received did not have a dust cap thing that covered the original strut mounts, so I washed it off, added some bearing grease, and installed it to the new strut mount.
• When I was working on the rear shocks, there was no real good method to tearing the sound proofing covering the shock mounts. It's hidden away by the trunk carpeting, but it still bothers me knowing that it's ripped up.
• If you go the route of Koni Sports (I really like them), be patient adjusting the rear shocks. There is no easy way to measure so you just have to turn one to the desired stiffness, then eyeball the other one until they rebound at the same rate. They're roughly 3/4 turn from soft on all four corners in my car. They supposedly will soften up a bit after a thousand miles or so.

Overall I encourage anyone looking for a similar-to-factory feel and with the time and money, suggest this suspension refresh. If you have any other questions, feel free to ask.

EDIT: I forgot to add that I did not include or replace the "upper spring pocket with spacer" (item 7, here: http://www.realoem.com/bmw/enUS/show...diagId=31_0408, part no. 31326769667) because no one mentioned I should nor did it seem necessary. Some other people might do it, but I did not and there seems to be no issue thusfar.

[ELCID86]

Great advice. Several of us are planning refreshes during the spring Koni sale. Colin's OB car is now a candidate...


Thumbs, iPhone, TaT.

[danewilson77]

Great advice. Several of us are planning refreshes during the spring Koni sale. Colin's OB car is now a candidate...


Thumbs, iPhone, TaT.

+1

Sent from my SM-G925V using Tapatalk

[NoVAphotog]

Great advice. Several of us are planning refreshes during the spring Koni sale. Colin's OB car is now a candidate...


Thumbs, iPhone, TaT.

+1

Thank you William, it is threads like these that make this forum incredible!