Coilover conversion
 

Hey guys, I have a 2006 4.8is with air suspension issues. Rather than deal with it, I want to swap it out. I see some coilovers say they aren't for cars with air suspension, some say with rear air, etc. I need any kind of tips you can offer and want to know what you have installed if you've swapped out the air. Looking at BC Racing coilovers but they don't mention anything about air. Also not sure what set they offer would be good as there is more than one. I'm aware I'll have a warning message on the dash but I can deal with that later.

KW couber or Bac racing are good choice .
After all you still need to re-code/re-write the VIN to let the computer know that car now without Ari suspension .

Swapping out the air shocks to springs shocks is not a big deal , but re-code the VIN is pain in the azz

The dirty solution is to code out the errors with inpa. Air will still be there, but no more messages.

So if I order the BC Racing coils, is there anything else I need to finish the install?

depending on how low you want to go you will need spacers in the back to increase the height... (i know i needed to for my KW v3's which i will be removing from my car shortly to sell second hand) and also rear toe and camber arms that are adjustable. this will help you dial in the rear wheels where you want them.

Small world, just picked up KWv3's for my E53, and am from CT as well! Were you parting out anything else from the vehicle?

My cousin also has a set of KW's on his E53 from 8 years ago.

You will also need these bits for the rear conversion:

prob just pulling them off to sell individually.

If you go with the two piece setup you will need the mentioned parts.
BC has a set where they do the spring right over the shock (unlike the V3 which have the separate spring.)

Who sells quality toe and camber arms?

only two that i've seen that people seems to like is the Hardrace brand and also the Thayer Motorsports brand.

Not cheap, but really the right way to go about it.

I went with Thayer Motorsport Camber and Toe arms. They were more expensive than the other arms (Hard Race and Megan also make kits), but it was nice to know my shop already had an account setup with Thayer as they purchase a lot of track related items from them for the E46 and other BMW racecars.

The pieces were very well built, and I was able to achieve factory alignment while still being lowered almost 3-4 inches.

I used Hard Race arms with no issues now in almost 2 years

Not needed if BC coilovers on all four.
 

I just replaced air on all corners of my 05 4.8is with the BR kit from BCRacing. It has coil overs on all four so these parts aren't needed. I would be interested to know if there's a cover for the rear air spring hole that doesn't have the air hose going down through the middle of it. Might be called duct tape over the hose hole.

I used 3 layers of aluminum backed butyl (sound deadening mat) cut to size and adhered. Works great at sound insulating and of course sealing the hole from the elements.

Smart. Thanks. I'll do that.

Dialing in BC Coilovers on 4.8is?
 

Are there any recommendations for the right number of clicks or ride height when installing BCs on a 4.8is? I may just need a good alignment but regardless if I go 5 or 15 clicks (soft-firm) on the shocks all around it feels...no real words for it...just kinda sketch on the freeway. Sorta loose and "sway-y" in the rear end. On the other hand, it's amazing on the dirt roads around (where it was always scary with the air before). Would there ever be a reason to have different shock settings in the front vs the rear? (there are 30 "clicks"). The install instructions said not to touch the springs. Should I? Maybe stiffer in the rear at least?

Also, my air system was all screwed up before I swapped it out so I couldn't measure what the "standard" ride height is supposed to be. It's definitely lower, now. If I'm not trying to achieve anything other than reliability, is there a recommended ride height (like stock that I should aim for, and should it be the same in front and back, and measured at wheel well tops or what)?


Thanks!


Update: Just found this: https://xoutpost.com/bmw-sav-forums/...m-removed.html. Super helpful, thanks!

Glad the info helps someone. I ended up leaving the ride height at those measurements. Love driving the truck. I ended up 10 clicks from hardest for my final ride stiffness setting. It's a tad bumpy over poor pavement, but still comfortable enough to not be jarring. My wife hasn't complained, though she does prefer a sportier ride, so take that for what it's worth. On smooth roads it's awesome.

@crystalworks: So far your recommendations have all been golden. I'd been fiddling around at 5 and 15 clicks from soft but at 10 from hard my wife's trip to Starbucks went back to "normal". So success. I'm also ever-increasingly pleased. With the many dirt roads around these BC coilovers are just so much smoother over the little bumps even when the shocks are set on the stiff side. My hunch is these springs are more progressive than the air springs were? It is still a touch skittish on freeway chatter but I haven't put the 50 lbs of sliding rear tray and trim back in so that may settle things.... So anyway, thanks. Happy.

Also, I'm sitting at exactly 27" all around (bottom of rim to plastic trim). My trim is the black plastic version (2005 4.8is). I think I'll raise it an inch around then get it aligned. Mainly because I also run snow tires that have a slightly larger radius. I'll work on uploading some pics.