The front and rear firmness settings were increased prior from setting out from the office. This worsened the bouncing-cartwheeling to the point the rear fenders were rubbing in to the tires on every dip of the road. The adverse increase in dampening actually locked out the shock from dampening, causing the car to bounce on the springs and frequently rub the fenders and tires. The decision was made to go in the opposite direction...soften up the dampening...so the dampening went from 30 front-27 rear (from softest to hardest) to 20 front-20 rear. This returned shock dampening and less spring bouncing, and an enjoyable balanced ride at speeds and cornering! Though I've not tested Yellow Speed Racing Sport coil-overs without a W220 front sway bar, it's strongly suggested to add this as a means to assure firmer cornering abilities while using modest dampening settings. In summation and IMO, Yellow Speed likely did some homework tuning/designing this coil-over strut package with the W215 chassis.

 

The suspension settled a bit and I'm beginning to understand its dynamics. With one index finger fender to tire clearance of the front wheels and two for the rear: An opposite direction of adjusting the dampening is taken: the front is now set at 17 from softest due to 25 causing a bit too much road feedback and causing the rear to excessively bounce. The rears were left at 20 from softest. This combination is yielding improved and decent drive-ability but somewhat still inadequate handling and road manner dynamics on roads that have dips. At the present height, moderate dips in the road sometimes bottom out the car. At the moment, until the rear fender to tire height is lowered 1" for looks and decreasing spring rebound and/or increasing spring pre-load to increase spring compression, my opinion is to go with higher rate springs to address the rear bounciness. There's a spring company that visited this thread that offers higher rate springs. This coming week the mechanic is lowering the rear 1" and decreasing the front's -2.3 degree camber...reporting back results.

 

With the front lowered to 25.75 inches from ground to bottom of fender, wheel alignment revealed -2 degrees front camber. Prior to 4-wheel alignment, stock MB camber bolts were placed in the front W220 lower control arms, and in the stock rear lower control arms. Turning the camber bolts, the technician was able to bring front camber to -1.5 degrees. Raising the front 1" to 26.5 inches brought camber to spec. and still gave a lowered appearance. The rear height was left at 27.5 inches, an inch higher than my liking. Dampening: from softest setting; 20 front, 15 rear. Road manners and handling: flat roads with corners felt smooth and handled with ease. At high speeds (75+ mph) moderate road dips (troughs) caused the suspension to bounce excessively. The Rennen's fitted with 295's and spacers rubbed with the outer lip of the fenders. This loss of suspension control at 75+ mph got hairier with corners with moderate road dips...the bouncing caused the rear to almost slide out and the front to under steer. The ride home from office: dampening was set at 25 front, 20 rear. This firmed the ride a bit but an absence of moderate dips in the road didn't allow for testing road manners at 75+ mph. The car handled corners better when it was lower and front camber was -2 degrees. The next ride height adjustment to lower the rear will necessitate another alignment, here I'll instruct the technician to allow for a small amount more negative camber, perhaps -1.5 degree. Tomorrow the front 255/35 19" Yokohamas are being replaced by Hankook Ventus to match the rear Hankook Ventus 295/30 19". Impression: despite continuing to adjust the Yellow Speed Sport coil-overs, the weight of the 2003-06 CL55 AMG may be too much of a match for the YSP 20k/14k struts/springs, this despite losing approx. 100 lbs. from deleting some exhaust and all ABC suspension components (next week the car will be weighed; 4250 lbs to 4150 lbs?). Higher rate springs? If this; will they overcome the strut dampening. As an attempt to lessen bounce, the next trial involves lowering the rear 1" to 26.5". If this proves to help, the rear fenders will have to be rolled as a means to clear the tires under full compression. From install, the YSP have approx. 400 miles on them. Today the Strut Master ABC delete module goes in to turn off all ABC warning messages.

 

Friday; on went a pair of front Hankook Ventus 255/35/19. This resolved the chopped ride of the former failed ABC destroying the front Yokohamas's. Best damper settings so far are: front 23, rear 19. For now, this seems to yield best compromise between firm yet comfort ride quality. This week; the rear will be lowered .5". This brings the ground a distance of to 27" to lip of rear fender. The front remains at 26.5" from ground to lip of front fender. This 2006 CL55 AMG possesses a Eurocharged Tuning Stage II (headers, 77mm fsp, etc., which yields 610 chp @ 675 lb/ft. torque, a DTK TCM tune. Near future mods are 82mm throttle body and 550 injectors; to yield a Eurocharged Stage III certified claim of 650+ chp @ 675+ lb./ft. torque, and a Quaife LSD.

 

If anyone swapping in coil-overs and removed the ABC components then experienced clunking-rattling sounds from the passenger rear area: this's caused by the rear ABC accumulator mounting bracket. It's in the trunk, located just above and right of the spare tire well, under the trunk floor cover. Lift and remove the trunk cover. The bracket is completely flat and black, so it can be mistaken as trunk floor. it has three bolts welded to it that go through the floor of the trunk. If you removed the accumulator that it once held, then there aren't nuts on the opposite side (facing the road) to hold it down. It will bounce off the trunk floor making a rattling and clunking noise that you'll swear is suspension related. Just lift and remove the bracket off the trunk floor.

 

I own a 2003 CL55. I just installed my yellowspeed coilovers. Before installation, I shortened the rear struts as short as I could....screwing the lower half into the upper strut. At its shortest setting...it was still just as long as the factory ABC rear strut. Is this correct? Did I receive lower halves that were not threaded all the way? They only screwed so far until they reached a stop/no more threads. So after installation, my rear is too high. I can only lower it by removing all of the preload and dropping the collar down a further 2 inches or so. Then.....it drives like crap. Rear bangs with every bump and bounces like crazy. Someone with yellowspeed experience please help. I've owned a previous CL500 and installed strutmaster. I did not like the rear height. And zero adjustability. Now...on my CL55 I'm dealing with the same issue. The rear sits up 2 inches from the 20" rear tires.

 

Ok. Yes, the coil-overs are as long as the ABC struts. The car is on a lift or jacked up to allow the rear wheels to drop all the way down to allow the strut install. The spring pre-load collar was unscrewed; releasing the factory set pre-load. At this point we'll have to measure then send you the distance in mm from the top of our rear struts to the bottom collar so that you can re-gain an accurate depiction of pre-load, or...you'll have to return the struts to allow them to re-set pre-load. Before installing the rear struts place the dampening adjuster knob in place on the top of each strut. Not doing so will not allow the dampening adjuster to be placed on after installation due to the rear glass sloping very close to the top of the strut, not allowing the pin of the dampening rod to be inserted. This Monday my 06 CL55 is going in the shop for new rear sub frame bushings. Measurements and pics for the top of the spring to bottom pre-load collar will be taken for your reference.

 

I just realized my mistake. After disassembling the rear strut.....the threading stops but it is a larger diameter and continues to thread mast that. I met resistance and so I stop twisting. Lol.....thank you for your input. I love these forums!!!

 

Awesome! Please report your impressions of YSS coil-overs. My install hasn't worked out to satisfaction due to the rear subframe bushings were too worn out and broken, allowing the rear of the body to bounce off the chassis. They were replaced yesterday...picking car up...will report findings.

 

Preload or no preload? With no preload and about 1in of space, it bounces wildly and bottoms out stroke of shock. Which will damage them. Enough preload to seat the spring and it's a nice ride. Extra preload and it stiffens or firms the ride. What's the popular setting here? I received 20F 16R springs. I have my 03 CL55 dropped pretty low. About 1/2" front tire to fender and 1" rear. I'm not overly concerned at this point about rubbing because I just ordered the widebody kit which will involve cutting the rear fender. Also, what is the effect of under damping or over damping? At softest setting (0F 0R) it floats nicely. But makes weird fluid sound on bumps. Lol. Harder setting (32F 30R) it bangs hard on bumps and makes noticeable noise in rear. So now I'm playing with mid settings. Currently 20F 15R. I'm on Mercedes AMG 20" rims. Once I install the widebody kit and new wider rims with hubcentric spacer....then I'll do alignment. So much to do...lol!

 

Can anyone tell me what caps they used to cap off the ABC system on the four corners? I think I am going to do this conversion, tired of replacing blown lines! Part numbers and where you got them would be awesome!
Regards

 

I chose to remove all the abc lines in my car. My previous CL500 I capped the lines off with I believe 3/8 brass caps from Home Depot. But with my CL55 I took out everything ABC related and sold most of it on eBay. By removing ALL ABC components, you shave off maybe 100-125 lbs (including swapping the heavy tandem abc pump for a much lighter S500 power steering pump).

 

@400rwhp,

Home Depot part.
“The hydraulic lines needed to be capped (3/8" brass female threaded pipe flare caps) and zip tied to parts of the chassis.”

Hope that helps. Op.

 

That's perfect, thank you. The power steering pump you used, what year S500 is it from? And did it swap in directly, as in no modifications needed, just plug and play?

 

Sean,
Do you offer 20kg springs for the Yellowspeed coilovers on the rear of a CL?
Rick

 

[QUOTE=principledchiro;7151508]Just an fyi, I completed my Yellow Spring Racing coilover conversion about two weeks ago now. I ordered the 20kg spring rate for the rear coilovers but, I'm discovering that they are a little too stiff for what I'm looking for. I'll be replacing them with 14kg springs in a few days but thought I would see if someone on the forum would be interested in a set of 20kg springs. BTW, these are on a W220 03 s600 TTV12. Please PM me if anyone is interested.

 

I have an 03 s600 with Yellow Speed Racing coilovers also. My spring rate is now 20kg in the front and 14kg in the back...tried 20kg originally in the back but was too stiff. Just wondering if your damper settings are still 23 in the front and 19 in the back, as I can't seem to get a good balance between normal surface street driving and higher freeway speeds...either a little to stiff or too bouncy still. I realize our cars are not the same in weight or weight ratio but, it seems you have experimented as I have with damper settings. Strange, the settings don't seem to be consistent or predictable...at least my impression. Your current thoughts and opinions would be greatly appreciated. BTW, I'm on 275/40/18 on rear tires and 255/45/18 in front at about 26" to bottom of wheel arch in front and 27" in back.

 

Out of curiosity, what were thethe spring rates for your front and back set up? Also, when you say "no preload," do you just mean hand tighten just until the spring is not loose or add aleast a spanner wrench's worth of preload. Lastly, is the preload that you recommend, different than the way they come from the factory?

 

 

 

so Yellow speeds ship out with 14kg Front and 10kg rear spring rates? and most people say this can be bouncy?

looks like i'll ask for some 14kg front and 12kg rear rates... and then add a front sway bar.. no rear sway bar

i remember reading that 20 front 20 back was way too stiff. i wish we had more info on kits between 14/10 and 20/20...

 

Here goes my completed 2003 CL55 AMG Widebody W215 with 20x12 R and 20x10 F ROHANA RFX5 Wheels on YellowSpeed Coilovers.

 

 

Beautiful car Man!