Hello, newish owner of a white 2006 CLS 55 AMG. Picked it up back in November with about 95k on the odometer. I don't have any pictures yet but figured I'd start a thread to document everything I've done so far to the car in case new buyers are interested in what to expect as these cars become more affordable.

When I picked up the car this was the list of issues I found after a pre-purchase inspection thanks to Eurocharged Austin:
Items fixed:
Dead intercooler pump (replaced with Bosch unit)
Trunk motor and controller were broken (replaced with used motor and controller)
Suspension bushings were shot (replaced all bushings and related components)
SBC pump failed (replaced under extended Mercedes warranty)
Gas tank leak (replaced under extended Mercedes warranty)
Transmission needed service (did service and 13 pin connecter)
Transmission mount was bad (replaced with new unit)
Driver and passenger window regulators failed (replaced with new window regulators)
Coolant expansion tank replaced
Valve covers resealed
Alternator replaced 7/5/19
Valve cover driver side breather cover resealed
Air intake tubes replaced
Replaced both front air struts with Bilstein struts
Replaced airmatic valve block
Replaced rear air bags with Arnott air bags
Replaced rear shocks with Bilstein (to keep ADS)
Replaced heater changover valve
Replaced cowl grille (the part that deteriorates at base of windshield)
Right side torque strut
Supercharger Rebuild
Alternator replaced again 7/5/20
Replaced aux battery in engine bay
All new brake pads/rotors in all four corners 9/30/20
Replaced both flex discs 1/21/21
Replaced both front O2 sensors 1/21/21
Replaced all idlers and tensioners with OEM 1/21/21
Replaced rear main seal and all parts associated 1/21/21
Replaced ECU 3/28/22
Replaced torque converter 3/28/22
Replaced OEM alarm to fix battery drain 5/20/22
Replaced OEM power steering pump and reservoir 06/03/22
Replaced OEM radiator and thermostat 09/26/22
Replaced headlights 11/14/22
Replaced driver window switch unit 11/14/22
Replaced passenger side defrost module 11/28/23
Replaced alternator again 11/28/23
Replaced lateral acceleration sensor 11/28/23

Not fixed yet:
Active headlight inoperable warning, due to bad motor in passenger headlamp
Sunroof wind buffer is broken, won't pop up
Passenger side defroster not blowing on windshield

Upgrades:
Large Eurocharged heat exchanger
Eurocharged 83mm supercharger pulley
Eurochaged ECU tune
Replica AMG 507 wheels 19x8 et 35 front, 19x9 et 35 rear Replaced with Vossens below

East Cost Euro motor mounts
American Racing long tube headers with 200 cell cats
1 step colder plugs
550cc injectors
Eurocharged ECU re-tune for headers and injectors

82mm Throttle Body (replaced used 82mm with brand new OEM 82mm)
Eurocharged ECU re-tune for throttle body
East Coast Euro secondary air injection block off plates

OEM+ NAG1 built transmission from Southern Hotrod
Upgraded valve body from Southern Hotrod

Single fin grill
Vossen VSF1 19x8.5 et 30 Front, 19x10 et 36 rear

Hardwired Valentine 1 radar detector
Custom RaceIQ tune (to deal with 82mm throttle body hiccup)

Future:
Lighter wheels that sit more flush, thinking 19x9 front and 19x10-11 rear but haven't figured out what offsets I'll need to make that work
CWA-100-3 heat exchanger pump

As of 2/6/19 it was putting down 453 HP and 521TQ on a Dynojet dyno at Eurocharged Austin. I've been lucky to get between 18-19mpg with a mix of highway and some city but I don't really get on it too often. I miss not having bluetooth but luckily the car had an aux input so I just use the phone to play Spotify through that. So far its been my daily driver and day trip car and to that regard it has been fantastic. Hopefully I can start getting away from the repair work so I can finish adding the go fast parts.

Put down 506 hp 540 tq as of 6/22/19 (headers, injectors)

Put down 537 hp 550 tq as of 12/27/19 (82mm throttle body)

Currently putting down 506 hp 577 tq as of 11/14/22. (RaceIQ tune, higher IAT due to weather left some HP on the table)

 

 

Just a quick update.

Picked up a BlueDriver ODB2 bluetooth scanner and started monitoring boost and IATs. In the 90 degree heat I've noticed that I'm usually around 18-19 degrees over ambient. I had an 8 second pull that got IATs up to 137 and it took about 1 minute to get the IATs back down to 109.

If anyone is wondering the BlueDriver ODB2 scanner DOES NOT work with the Torque App so don't bother paying for the Torque App like I did. That was a bit of a bummer.

Hopefully in the next 3 weeks I will be getting some American Racing long tube headers with cats, 550 injectors, 1 step colder plugs, wires, and tune installed by Eurocharged ATX. I asked to get a before and after dyno pull to see how much the headers add to my current set up. This is likely my last power mod and an attempt to help address the heat over the summer since the headers should help lower the boost a tad.

I'm also posting the dyno chart of my car shortly after getting the 83mm pulley, heat exchanger, and tune





.

 

I also forgot to mention with the 83mm pulley I'm seeing almost 25 PSI of boost at wide open throttle and usually about 3-4 PSI of boost on light throttle or just idling. This seems a little odd. Has anyone else noticed that?

 

You need to deduct 14.7 psi (ambient atmosphere air pressure) from your reading. There should be a setting on your logging app to toggle it or you can put the value in yourself.

 

Thanks for the info. I looked up the atmospheric pressure where I live and it was about 14.65 psi. Deducting that from my logged high pressure of 25.5 psi, I'm looking at about 10.85 psi of boost with the 83mm pulley. Looking at some of the posted pulley boost charts in the E55 forums, that seems like the boost is low for that pulley. I'll go out and make another pull or two to get closer to redline and see what boost I get there.

 

Peak boost occurs during 3rd gear I believe so you'll need to rev out that gear to get your best reading. Those charts are good for comparison but there is plenty of variables at play, charge air temperature, belt slip, altitude to name a few..

 

Why you getting colder plugs?? 98% you will need them as these cars run perfect with stock one's.Colder plugs are needed when the heat range is needed to step it colder as it have issues with melt or blow out. ..Many get colder plugs cause others think they need as it's becoming a urban myth of he said she said rumor's. These cars fyi got 2 plugs per cylinder which it create as more efficient complete burning plug ..

 

The plugs were recommended as added insurance with the mods I'm running and especially dealing with the heat of a Texas summer. I didn't think there was that much of a downside with running the colder plugs.

 

You probably know this already, but the ecu starts pulling timing at 95*

 

Just a quick update before the weekend and a before and after dyno of the car. Both dynos were done on the same dyno during the same hot week in Texas (in the 90s)

Blue line is the car with:
83mm pulley
Eurocharged XL heat exchanger
Eurcharged Tune
Stock headers, cats, exhaust

Red line is the car with the following added:
American Racing long tube headers with 200 cell race cats
550 injectors
1 step colder plugs
Eurocharged Tune

Haven't had a chance to pick the car up yet to give feedback on the noise or any vibration of the East Coast Euro motor mounts but I'm pretty happy with the results.
East Coast Euro motor mounts

Gains look like 33 ftlbs of torque almost across the entire rev range and 60 hp peak with a pretty considerable margin across the rev range.

 

Yeah that nice are they both eurocharged dyno tunes?

 

Yep both tunes were from Eurocharged.

 

Picked the car up this morning and some quick observations after driving it around all day in 95 degree humidity.

East Cost Euro motor mounts with the softest polyurethane:
Hardly any super noticeable vibration. If I'm really looking for it I can feel a very very slight vibration but nothing that is making everything resonate and rattle inside the car, pretty close to their claims of near factory comfort. I had motor mounts in fair condition for the mileage so there was a slight improvement when getting on the throttle. I was told that the mounts sat maybe 10mm lower than the OEM mounts which gave the American Racing Headers a bit more room for clearance.

American Racing Headers with 200 cell race cats:
I was worried that the car was going to be too loud going to these headers but with the windows up, and even with the windows down they are not that loud. Definitely louder than the stock headers but if you're not getting on it they're pretty tame. No noticeable drone at cruising speeds and a slightly louder rumble from a stop or accelerating. As far as performance goes, the car feel much more responsive. I barely have to give it much throttle and the thing takes off. I did a couple of pulls on the highway and even with IATs north of 100 degrees the car felt like it had much more top end than previously. The above dyno certainly shows it.

I'll be keeping an eye on the gas mileage over the next few weeks. My initial suspicion is that the OEM MPG calculator is no longer calibrated with the 550 injectors so I'll be doing it by hand.

 

Nice numbers man.

 

Just got back from a 2385 mile road trip with the CLS and kept track of all fuel stops and mileage. As suspected the car's MPG calculator is no longer accurate with the 550cc injectors, headers, and tune.

First I calculated MPG using the mileage from the trip computer. On average the MPG shown on the "Since Reset" page of the trip computer was off by 10.64%. The worst it was off was 20.055%, least it was off was 6.73%, and a median of 8.85%. Average MPG was 18.37.

Second I calculated MPG using the delta between odometer readings. On average the MPG shown on the "Since Reset" page of the trip computer was off by 9.28%. The worst it was off was 13.06%, least it was off was 6.73%, and a median of 8.45%. Average MPG was 18.76.

The trip was a good deal of highway with a little bit of city driving mixed in at the destination.

The only hiccup in the whole trip was that the alternator went out on July 3rd, after the dealers in Phoenix had closed and would be closed on the 4th. Symptoms that tipped me off something was wrong was the AC immediately started blowing hot air from all vents, the vented seat buttons were flashing, the "Low battery, convenience functions unavailable" message came on and there was a slight burning electrical smell under the hood. MAJOR shout out to Mercedes Benz of Scottsdale as they were able to get the car fixed in a few hours on July 5th so that I could return home. They even detailed the car for me

 

Great job with the build!

 

Awesome thread, very helpful information and again great numbers.

 

@tw2 Thanks, I spent quite a few months on the forums lurking and reading damn near every thread related to the CLS55 and E55s trying to figure out a game plan for my mods. This thread is just a feeble attempt at giving back to the community.

 

I have been keen to try the poly mounts but I don't want any extra vibration but it sounds like it is comfortable for daily driving. Thanks for the feedback.

 

Nice build! Good tip on MPG calculation on dash behind off with larger injectors. Did you do a looped fuel line?

When I get around to doing headers I think the 10mm lower mounts are the way to go.

Enjoy!

 

Thanks @CDC55AMG . I did not do the looped fuel line when I had the injectors upgraded and headers added. I don't think I'm going to be anymore power mods for now. If anything I'll be looking at just fixing little things like the headlights, some rattles, etc. Maybe a little more cooling mods but nothing major like trunk tanks or anything like that.

 

You're welcome, do you have a split cooling system? It seemed to be pretty popular when it came out but my take perception of that take is that it's mostly beneficial when adding volume to the intercooler system via trunk or under hood reservoir tank. I ordered a secondary heat exchanger from VRP to add to my CLS55 in conjunction with the stock cooler. I will install when I do a Bosch 010 pump swap for a factory pump. Your setup is very close to what I would like to do; proven and reliable performance without going hog wild.

 

@CDC55AMG No split cooling here. Just the larger heat exchanger from Eurocharged replacing the stock heat exchanger. I can't wait till we start getting some cooler temps here in Texas my IATs are usually around 100-115 during the day here with occasional spikes up to 130-140 if I get on it (which I try not to do in the heat)

 

Adding to the list of stuff to fix:

1) Ordered new Air Inlet Tubes, when I was cleaning the engine bay, I noticed that both tubes were cracked almost all the way around in the accordion section. Dealer wanted $35 each, picked them both up for $41.03 including shipping from www.mbpartsonline.com
2) Ordered single fin grill from www.55tech.com in attempt to give the front end a little more modern look

Currently looking at a used set of 19x8.5 and 19x10 Vossen VSF1 wheels as an upgrade from the replica 507 wheels that are on there now.

Has anyone had any luck running a 265 front and 295 rear combo?