BC Coilover Setup: Compression/Rebound Settings, Ride Height Adjustment, Camber, Etc.

[fostersafb]

Ok, so I got the BC's installed today, now as long as I installed them correctly its time for all of the setup configurations.

I'm hoping to get a discussion going about some of the BC coilover specifics. I'm not sure how many of us are running them but considering their quality and performance vs. the price they should receive a little attention.The adjustable options that I think need some focus here on the forum are:

1. Front camber settings
2. Front and rear rebound/compression settings
3. Ride height adjustment
4. Spring Preload

For those that are running them, please chime in on how you have yours setup and any other configurations you have run with them. I'm just beginning the process so I cant offer much aside from what I came across today.

First, the instructions that come with the coilovers are a joke. They did not provide one bit of usefull info.

Secondly, I'm not sure if I installed something wrong, but the tab that holds the speed sensor in place that mounts to the end link tab on the strut housing sticks out about 1 1/2" from the strut housing itself. It was far enough to come in contact with the inner bead of the rims!

Third, I have read that the front struts come already with the correct preload, however they were both different thus adjustments had to be made.

Fourth, the rear setup needs its own detailed instructions. I just about put my head through the wall trying to figure it out. Along with the correct install orientation, the ride height adjustment needs some light shined on it. Unlike the front, the spring and strut are separate and both have their own height adjustment. I don't know if one rotation of the spring perch collar equals one rotation on the strut adjustment?

Lastly, related to the rear height adjustment; Is there a way to adjust the spring perch height without completely uninstalling the spring itself?

Anyways, most of what I did today was just a shot in the dark. Obviously I have a lot of questions that need answers. I will update this thread as I receive info from BC or anyone else. This is all in the hopes that anyone else who decides to take on the install and setup themselves will have an all inclusive resource to reference.

Thanks.

 

[CnoTataymo]

1) I run mine as close as possible to stock since I want pretty even camber wear.
2) 9 front/10 rear but recommended from SU and others are 12 front/15 rear
3) Fronts are easy just like any other setup but the rear, you'll have to unbolt the bottom of the shock, lower control arm and rear sway bar endlink and finally access the perch/spring.
4) ?

 

[fostersafb]

1) I run mine as close as possible to stock since I want pretty even camber wear.
2) 9 front/10 rear but recommended from SU and others are 12 front/15 rear
3) Fronts are easy just like any other setup but the rear, you'll have to unbolt the bottom of the shock, lower control arm and rear sway bar endlink and finally access the perch/spring.
4) ?

Thanks again. It looks to me like the rear shock can be adjusted without removing. If you loosen the lock nut, the whole shock tube will rotate and shorten or extend on the lower threaded rod. The springs though, that another story, RSB has to come off and then the lower perch can be lowered enough to remove the spring.

I'm going to play around with them again today and see what happens.

 

[CnoTataymo]

Yeah, if you got enough room for your tools to adjust the height of shock, you don't have to fully remove them. If you shorten them, it won't really do anything to lower your car. Removing the endlinks is the easiest way to access the spring when you want to lower them. As for negative camber, there is obviously going to be more camber then stock. Probably -2.5 at the most.

 

[fostersafb]

I'm kind of at a loss right now. I adjusted the springs down to the lowest setting (collars threaded all the way down) and then by hand turned the shock body all the way down to the lowest point. It stopped with about 2 inches of threaded rod remaining. With that the rear is still only just over an inch lower than stock???

 

[STRICK-]

fronts go lower than the rears with the BC setup. BCs will only allow for the rear tires to sit flush with the qtr panel, not tuck.

 

[madvillian]

fronts go lower than the rears with the BC setup. BCs will only allow for the rear tires to sit flush with the qtr panel, not tuck.

which is a total bummer.. it seriously sucks, i wish id got the H&R's for that reason, but im not going to trade them out now.

 

[Wastegate13]

which is a total bummer.. it seriously sucks, i wish id got the H&R's for that reason, but im not going to trade them out now.

There's no way in hell you'd ever tuck the tires on your setup anyway. What difference does it make?

 

[fostersafb]

Do you guys have your rears at the lowest position, both spring and shock? I worry that having it at the lowest might hurt their performance a bit.

 

[Wastegate13]

Do you guys have your rears at the lowest position, both spring and shock? I worry that having it at the lowest might hurt their performance a bit.

No, mine were actually perfect right out of the box. I measured them to make sure they were even side to side and put them in. I expected to have to make adjustments to the ride height to get where I wanted but I just lucked out.

 

[bykeryder4life]

I get confused when talkin about the dampening settings, is it the lower the number the harder the dampening? Or Opposite?

 

[bykeryder4life]

Secondly, I'm not sure if I installed something wrong, but the tab that holds the speed sensor in place that mounts to the end link tab on the strut housing sticks out about 1 1/2" from the strut housing itself. It was far enough to come in contact with the inner bead of the rims!

ya I had the same problem I grinded it down a little bit....

 

[CnoTataymo]

I get confused when talkin about the dampening settings, is it the lower the number the harder the dampening? Or Opposite?

The recommended from SU is 12 front and 15 rear. But I run mine at 9 front and 11 rear. The spring rates are 330 front and 220 rear. Just set it to what you like for DD.

 

[STRICK-]

ya I had the same problem I grinded it down a little bit....

i had to mod mine as well, i just bent it in some.

I get confused when talkin about the dampening settings, is it the lower the number the harder the dampening? Or Opposite?

lower number = softer ride
higher number = stiffer ride

 

[mspeed3420]

I just got my BC's installed and I have them set at 12-front 15-rear but I'm with these other guys that its a little too stiff for daily driving, Im going to change it to 9 and 12 and see how that rides. I also have 15mm spacers on their way because the wheels are way to far in and Im going to set the cambers after the coils set in a week or so.

 

[CnoTataymo]

You'll rub in the rear even with it rolled.

 

[wldchld]

can u get a rear drop like this with bc's?

 

[wldchld]

im thinking about leaving the rear the way it is and just put the bc's in the front. thats where most of my problem is. i think the shocks are blown cause my ride is bad.the back just follows. any suggestions?

 

[fostersafb]

So, I got some new info today from BC. We covered everything I had questions on.

Rear configuration/ride height/preload adjustment:

Ok so as far as ride height, the lowest they are intended to drop the MS3 is about even with the stock tires. Some may like it, other may want more. If more drop is needed you can remove the lower collar and basically just have the spring sit on the perch and plastic washer. This will drop the rear about 1/2" more.

Rear preload is set pretty specifically. You have to unbolt both the spring perch and lower shock mount. Once everything is unbolted and loose you position the spring collar at your desired height and assemble the collar/spring/donut in the spring perches. Using a jack you compress the spring to the point where both the top and bottom are in contact with the upper and lower perch. While doing this grab the spring and try and wiggle it around. Keep compressing the spring by using the jack until the point where the spring does not move vertically or horizontally. Basically you are trying to bring the spring to max rebound without being loose. Once you are there throw in the bolt that attaches the lower spring perch to the knuckle. Now you raise or lower the shock mount to line up with the mounts on the knuckle. Once you get the shock mount and knuckle mount lined up, throw in the other bolt and tighten her up. Loosen the set nut on the shock body. By hand turn the shock body clockwise, which will shorten the shock. Continue this until you begin to feel some resistance. As you are turning it, more compression is applied to the spring. The resistance you feel is the proper preload on the spring. For me it was about 10 turns. The theory behind matching the height of the shock to the level established by the spring at max rebound is that in driving situtuations where max rebound is achieved you dont want to limit the available shock travel by having it too short. The same applies to compression. If its too short you will just hit the bump stops.

Also, worth noting is to periodically check the tightness of the supplied 19mm bolt that mounts the spring collar to the lower perch. I guess people have had it work itself loose or fall out. Torque it down pretty good (they didnt have any torque specs). I tightened mine to about 100ft/lbs. If yours keeps coming loose, just add some loctite.

The front is pretty self explanatory. They are supposed to come preloaded from the factory but in case you have to adjust yours they recommend a 5mm preload compression. Basically, raise the top adjustment collar until it secures the spring where it does not move vertically at all. Once its held in place rotate the second collar until it touches the top collar. While keeping the second collar at that same height, rotate the top collar to raise it 5mm above the second collar. Once you get the 5mm raise the second collar and lock the preload collars together. Then you can do what you want with the third height adjustment collar.

I ended up removing one of the collars from the rears and adjusted the shock 15 turns up from the lowest point. I also set the front preload and dropped it another 5mm. I'm still running 12/15 but may adjust it a little softer,maybe 9f/12r.

Once they settle and I get her aligned I'll post up some pics. Hope this helps.

 

[fostersafb]

can u get a rear drop like this with bc's?

Yes, if you remove the lower collar from the rears. I'll post up pics of mine soon.