sakodik

WITH THAT SAID... I would suggest sticking with stock, less headache, no money lost, no worries about MAYBE it working or not. W220, huzzah.

tusabes

yes if you're going to do the same size on all four corners on 18s , 265/40/18 is the best size

if you are doing staggered 18s it's still better to do 245/45/18 front and 275/40/18 rear

Often people put the wrong smaller tires on, 245/40/18 front and 265/35/18 rear , probably bc because these sizes are much cheaper

TenZero

Yes, that's correct. When this set of tires is done, I'm thinking I'd like to try 275/40 or 275/45/19 on 19x9.5s at all corners. Aside from the reported handling improvements, I'd like to have a bit more sidewall, and being able to rotate tires would be nice on a 500hp car.

AlexMercedes

If you still have all the fiber optic cables in tact - like I do - then it is possible to revert back to the stock system. However, I wouldn't recommend it... the damage is already done. I wouldn't go through the huge hassle of tearing apart the interior and reinstalling every single stock equipment when someone already spent a lot of money to have it all changed anyways...

The problems I'm having with white noise and earbleed is because of a crappy amplifier and no subwoofer, which can be fixed with money (like all things). However, the loss of functionality in the instrument cluster cannot be fixed, you just have to live with it. For the tire pressure monitoring, I would say just get a good quality aftermarket TPMS that transmits data to your phone, like I am planning on doing soon.

Why don't you recommend the strutmasters? I was planning to convert mine to strutmasters whenever the ABC fails, but what about it makes you dislike them?

tusabes

People have reported car sitting too high after strutmasters conversion , having to cut coils which then results in rubbing and bottoming out as they use a soft spring

yellow speed is fully adjustable with no cutting

TenZero

My experience with Strutmasters in a nutshell:
Pluses:
1 Shipped quickly
2 My kit installed easily, fronts can be done in 10 minutes each side. Install videos on their website are really good, and useful whichever solution you go with, especially for the rears.
3 The supplied cap off hardware works well whichever option you use to cap the ABC lines.
4 Their dongle works as advertised to satisfy the ABC dash warnings, except the tiny lights on the ABC button. (use a sharpie)
5 Relatively inexpensive, and they will probably work OK for V8 car.

Negatives:
1 Kit was poorly packed for shipping. These things are heavy, and a couple of the boxes were shredded during transit, resulting in bent studs and missing mounting nuts. Not necessarily SMs fault. I was able to straighten the studs pretty easily, and use my own nuts for the install.
2 The #1 reason they are not a good fit for the 600: Even though they list the S600 application everywhere on their website, their tech support actually told me their kit is engineered on a V8 car. When I told them my kit was too softly sprung in front, and that I had a V12, they said "Oh, you didn't tell us you had a V12". They were actually unaware that ALL 600s are V12 cars. They have offered to make up a kit with a spacer and a stiffer spring, but on the same damper. For many very technical reasons, this is a half *** solution, and I am not confident in their ability to get it right at this point.
3 When I asked to speak to the R&D guy about the actual spring rate values and damping changes they were proposing, I was advised that R&D does not speak to customers, and that information would not be available. Pro tip: If you change spring rates, you better calibrate the damping accordingly, or have adjustability available.
4 Their proposed changes are based solely on the picture I sent them and are a complete guess, with correcting the ride height as the only parameter. Unsatisfactory to me.
5 You get what you pay for. I am ordering a Yellowspeed kit today. The guy I talked to was very suspension savvy, and not only able, but willing, to intelligently discuss my questions and concerns. I feel much more confident in this outcome.

You can see the front ride height is too low, from not engineering for the extra weight of the V12. It looks good, but it's too soft, and the suspension is already into the camber gain part of the travel. I also think that their 'custom' solution should be engineered more thoroughly than with just a picture, and they should be willing to discuss technical changes with a customer who requests the information.