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Discussion Starter #1
With pics would be great.

I have the BC's, but haven't fitted them yet. In all honesty the instructions are a little lost with being translated, and i was wondering if you guys could give me a quick heads up regarding the heighht adjustment of these units.

I've never had coilovers before and am aware of preloading springs etc and really don't want to do something to the 'overs thats a no no regarding incorrect method.

Basically i know there are 3 "nuts" or rings on the shock body. Top two locked together, obviously so they stay where they're put, and one ring at the bottom of the threaded section of the shock.

I initially thought that you would undo the lock ring and adjust the other, but i think that simply compresses the spring more, and am more inclined to think that the two locked rings are there purely to hold the spring in place with a slight preload, and the bottom collar holds the key to ride height.

A 3 sentence idiot guide with a pic would be appreciated
 

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Hope this helps:

1. Make sure both 2a and 2b are tight. These are locked against each other.
2. Loosen lower lock ring (2c).
3. Using the spanner wrenches that comes with the kit, turn the upper spring seat (2a) counter clock-wise (right to left) to lower or the lower lock ring (2b) clock-wise (left to right) to raise the vehicle.
4. After you achieve your desired height, make sure you tighten the lower lock ring (2c) before you drop the vehicle to the ground.
 

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4. After you achieve your desired height,

you complete this for ride height adjustments? so what's the knurled knob (+/-) at the top of the strut for then?

Mike
 

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4. After you achieve your desired height,

you complete this for ride height adjustments? so what's the knurled knob (+/-) at the top of the strut for then?

Mike
That is damper.
 

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Hope this helps:

1. Make sure both 2a and 2b are tight. These are locked against each other.
2. Loosen lower lock ring (2c).
3. Using the spanner wrenches that comes with the kit, turn the upper spring seat (2a) counter clock-wise (right to left) to lower or the lower lock ring (2b) clock-wise (left to right) to raise the vehicle.
4. After you achieve your desired height, make sure you tighten the lower lock ring (2c) before you drop the vehicle to the ground.

You dont have to loosen 2c. 2a and 2b only.

both ways will raise/lower the car, but with 2 completely different effects.

Adjusting 2a/2b can change your shock travel limits, so adjusting 2c is the way to go. Most coilovers adjust 2a/2b, and dont have a 2c
 

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both ways will raise/lower the car, but with 2 completely different effects.

Adjusting 2a/2b can change your shock travel limits, so adjusting 2c is the way to go. Most coilovers adjust 2a/2b, and dont have a 2c
I guess that depends on the coilover you have. I've never seen anyone who sets up suspensions adjust the 2c once the struts are on the car. On the Cross/Jic, the 2c doesnt have much range to move (basically it's there to get the strut to the correct length to fit) the only way to properly lower/corner balance the car is with 2a/b. You can also pre-load the springs the same way, but I would strongly advise against that unless you have progressive rate springs.
 

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Damper settings
ah OK thanks, believe it or not I've got a set to go on my car, just didn't realise you had to set up the ride height that way...........BTW the other day whilst driving I stopped the car as I thought 100% I had a flat tyre the back felt really disconnected with the road, kinda like it was going to let go any moment, all tyres checked OK, had a quick look around underneath nothing obvious to note, can only conclude that the shocks are totally knackered........good job got a set of BC's in my garage, just waiting until Jay Peers sort's his act out and fit his.........come on lad what you waiting for? your house must be like a new pin now!............
 

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Discussion Starter #10 (Edited)
Cheers Guys.

JUst had a good look around and called the guys at Corby where i got my BC's to put to them the 2 scenarios.

Both of you are correct in what you say, although with the BC's you only adjust the bottom nut, 2C in the picture, so you maintain full shock travel, and don't compress the shock at all to alter ride height as in say a KW shock.

The idea is so you maintain exactly the same shock travel capabilities/ride quality etc etc and don't compreomise it in order to acheive your desired height.

On the BC's (or other similar coilies with a locking collar at the bottom) you adjust it this way. For ones with just the 2 top lock collars you would adjust them as per Mike (E55)

Google Image Result for http://www.modernperformance.com/images/coilovercomparison.jpg


@Mike AKA Mr Devere. i've got to get on with it dude. House is finished and althoug i won't be doing mine til i get my DD and it warms up to above 32F, i don't mind cracking on with yours fella.

I'll drop you a text
 

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Okay guys. I am having a hard time raising the front BC coilovers on my car. I have spent hours in my garage the past couple of nights trying to raise the fronts and I am just lost. I even spoke with Mike, a representative of BC north America and he is perplexed as well. I am starting to wonder if my unit is jacked up or improperly installed. No matter what I do the car stays the same height..very frustrating. I started by first measuring the current height of the drivers side(NA) which was at 12.5 inches(a tad too low) from the hub of the wheel to the highest point of the fender.

After I took the wheel off, I marked a spot right above 2c with white polish before I started anything so as to ascertain my starting point. I also measured the distance between my starting point and 2b. I then loosened 2c to allow for ride height adjustment.

Next, I loosened 2a then 2b until the spring was freely movable then locked 2a and 2b together nice and tight again because I did not want to interfere with the spring pre-load while messing about the with height adjustment. I was saving that for last. I then proceeded to turn 2b clockwise while still locked to 2a and this made the body of the shock twist in the same direction as I threaded upwards. I also noticed that my starting point marked with white shoe polish begin to rise, so I figured I am making progress.

Well, my state of euphoria was short lived when I was done with the spring pre-load(5mm), tightening 2c, putting the wheel back on lowering the car jack because I was right back at 12.5 inches, where I started:dunno:. Its like magic I tell you. I have attached some pictures. I welcome any related advice, comments or educated guesses. Thank you all in advance.

Pic 1: Starting ride height
Pic 2: Starting distance
Pic 3: Marked starting point
Pic 3: Making Progress??
Pic 5: Height after adjustment


Vic
 

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Discussion Starter #13
Firstly, once the A & B collars are set from the factory they need never be loosened again unless you are replacing them. Certainly they bear no relation to adjusting ride height on this type of coilover.

So first off, sort the preload as described above, then leave them well alone.

Secondly to adjust ride height you need to loosen the C collar (the bottom one) and back it off right out of the way.

Then you want to screw the whole of the coilover strut into the "tube" part of the coilover that collar C locks against. and screw that into the tube section to lower the ride height, or screw it further out of the tube section to raise the ride height. Because collars A&B are still locked together, you can easily do this with the C spanner provided on collar A for your leverage to turn the strut

Once you have done this to your desired height, you can run the C collar back up against the "tube" and tighten it up.


Essentially the less thread you have showing between th B collar and C collar, the lower the car.

Do it this way and you will be able to raise/lower the car to your desired height easily
 

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Firstly, once the A & B collars are set from the factory they need never be loosened again unless you are replacing them. Certainly they bear no relation to adjusting ride height on this type of coilover.

So first off, sort the preload as described above, then leave them well alone.

Secondly to adjust ride height you need to loosen the C collar (the bottom one) and back it off right out of the way.

Then you want to screw the whole of the coilover strut into the "tube" part of the coilover that collar C locks against. and screw that into the tube section to lower the ride height, or screw it further out of the tube section to raise the ride height. Because collars A&B are still locked together, you can easily do this with the C spanner provided on collar A for your leverage to turn the strut

Once you have done this to your desired height, you can run the C collar back up against the "tube" and tighten it up.


Essentially the less thread you have showing between th B collar and C collar, the lower the car.

Do it this way and you will be able to raise/lower the car to your desired height easily
I loosened 2a and 2b because I attempted the height adjustment the previous night without touching them then loosening 2c to allow the shock body to move upwards. I had to turn 2b clockwise because that's the only way shock body will twist. It was impossible for me twist it by hand. I noticed that the spring pre-load changed that's why I loosened them this time as to not mess with the pre-load while doing the height adjustment. The pictures show that the shock body moved upwards, but this did not raise the car. I know what directions to turn to raise and lower the car...I think:hihi:. Its just not doing it. I also noticed this morning that ride has gotten stiffer almost jarring now.

I just don't understand what I am doing wrong. The recommended pre-load is 5mm and that's where its at no more no less. 2c is locked down tight every time before lowering the car jack. Do I have a deffective unit? I mean everything has been cool with the ride over 4k miles after install.

The only reason I even bothered with the coilovers was because I started hearing spring(doing, doing) noise from the front while making slow turns . So I read on here and other forums that the spring might be too loose and don't have sufficient pre-load. Hence, I set the pre-load to 5mm by loosening 2a and 2b till the spring was free then tightened 2a till the spring was snug. I then tightened 2b against 2a, then tightened 2a till there was a 5mm gap between 2a and 2b. I the locked 2b to 2a..pretty straight forward. That's where my night mare started. The car seemed like it dropped more in the front wheels. That's why I am now trying to raise back up. I sent an e-mail to mike with BC north America with the pictures. I waiting for hear back. There has to be something that is not adding up.

Vic
 

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After you make an adjustment, I recommend driving the car a bit and then checking it, you wont get a proper measurement after you let the car down off the jack.
 
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I made the adjustments and drove it work this morning(35 miles) and no change whatsoever. The only change is the ride is noticeably stiffer for some reason. I did not touch the damper settings knob in the engine bay. Could it be I am adjusting something else without knowing it when twisting the shock body? I am really clueless here:dunno:. It seems so straight foward.

Vic
 

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edit.
 

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Discussion Starter #19 (Edited)
I know it may seem like i'm trying to teach you to suck eggs dude, but you wouldn't believe the amount of times anyone can get what looks to be the obvious so wrong sometimes. Sorry if my post seemed condescending, it wasn't meant like that at all.

Basically in short short terms, the more thread of the coilover you see the higher the car sits, purely as in essence, the entire shock is longer and so it pushes the font wishbone further away from the top mount and in turn raises the vehicle right???

Are you sure that the "tube" part of the shock is clamped tight in the same place within the housing in the front wishbone/control arm???

I agree that from the pics you posted it looks as if you are doing this right, but we must be missing something obvious.

Can you adjust the coilovers to the extreme just to verify that you are altering the ride height, as in, take a base measurement for reference, but then adjust them in the collar so the car should sit stupidly high, and then again to make it sit stupidly low, and post findings/measurements?

Hang on i've had another thought also.

Can you confirm that when you are adjusting the coilover, that the whole "threaded" part of the assembly is also turning along with the A&B collars all together, whilst leaving the "tube" part still/clamped?

As you say the ride quality has changed and gone stiffer, indicating that you may have actually made the shock body longer, but compressed the spring by the same amount, in effect making it stiffer, but not altering the shock length and thus ride height at all.

Every single part of the assembly needs to turn apart from the clamped "tube" to alter the height. If something else is adjusting "out" whilst you are winding "in" or vice versa it would give the symptoms you describe
 

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I know it may seem like i'm trying to teach you to suck eggs dude, but you wouldn't believe the amount of times anyone can get what looks to be the obvious so wrong sometimes. Sorry if my post seemed condescending, it wasn't meant like that at all.[\quote]

No worries. Your statement did not seem condescending at all. Trust me, I appreciate your comments. I did not mean to sound like a smart *** either.

Basically in short short terms, the more thread of the coilover you see the higher the car sits, purely as in essence, the entire shock is longer and so it pushes the font wishbone further away from the top mount and in turn raises the vehicle right???[\quote]

That is correct. At least it sounds and looks logical to me.

Are you sure that the "tube" part of the shock is clamped tight in the same place within the housing in the front wishbone/control arm???[\quote]

Yes sir.


I agree that from the pics you posted it looks as if you are doing this right, but we must be missing something obvious.

Can you adjust the coilovers to the extreme just to verify that you are altering the ride height, as in, take a base measurement for reference, but then adjust them in the collar so the car should sit stupidly high, and then again to make it sit stupidly low, and post findings/measurements?[\quote]

Sounds like a lot of work but I'll give it a try. At this point I'll try anything.


Hang on i've had another thought also.

Can you confirm that when you are adjusting the coilover, that the whole "threaded" part of the assembly is also turning along with the A&B collars all together, whilst leaving the "tube" part still/clamped?[\quote]

Yep. As far as I know because I see it move and the markings on the the threaded housing elevate upwards out of the tube with A and B locked together. I have to use B to twist threaded housing.


As you say the ride quality has changed and gone stiffer, indicating that you may have actually made the shock body longer, but compressed the spring by the same amount, in effect making it stiffer, but not altering the shock length and thus ride height at all.[\quote]

That was the main reason why I made sure the spring was free before doing the height adjustment. So, the ride getting stiffer is beyond me because I did not touch the damper setting. This one is a head scratcher
.


Every single part of the assembly needs to turn apart from the clamped "tube" to alter the height. If something else is adjusting "out" whilst you are winding "in" or vice versa it would give the symptoms you describe
My sentiments exactly.
 
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