I've been extremely dissatisfied with the braking performance of my '04 E55. Besides the poor brake feel of the SBC Sensotronic brakes (i.e. they're not so easy to modulate as the brake-by-wire technology feels as if I'm stepping on a pillow, or as if the brake pedal is connected to the calipers via rubber bands).

As I've long ago done on my '00 BMW M5 (which is equipped with StopTech front brakes), I decided to have custom brake pads made for the E55, which utilize a racing compound, but one that is eminently streetable). What a difference they make to the overall feel of the car! Instead of having to press the brake pedal with much force (and long/far along its travel) in order for the brakes to bite, the brakes are noticeably more responsive! When asked, they now bite with immediate effect, even when cold.

I haven't measured stopping distances vs. OEM. However, I can categorically state that I can now drive the car with much more confidence, especially when driving aggresively on a mountain road. I feel much, much more secure in feeling and believing that I can 100% count on my brakes, especially in late-braking maneuvers. They flat out bite instantly!

Besides the massive increase in responsivity and bite, the brakes now feel less "squishy." With the increase in the cF (Coefficient of Friction), it now takes less effort to engage the brakes (i.e. the OEM pads probably have a cF of 0.35-0.38 vs. nearly 0.55 for the Carbotech Panther XP1108 -- sometimes referred to simply as XP8 -- units on my car).

The only tradeoff vs. OEM is the quick brake dust build-up that occurs on wheels after spirited driving. These pads squeal much less than the XP8s on my M5 due to the fact that Carbotech was able to retain the OEM anti-squeal shims fitted to the backing plates of the brake pads. The OEM pads have these shims rivetted to the backing plates. However, when removing the OEM pad material, it's necessary for Carbotech to separate these shims from the backing plates. (Luckily, they still are able to "click" in place despite the fact that these shims are no longer rivetted).

Carbotech was able to drill into the new brake pad material so as to accept the three OEM brake pad wear sensors. Therefore, there are no distracting error or warning messages regarding brake pad wear on the dash display

The other tradeoff is the cost. The first thing that needs to be done is to send Carbotech a set of OEM "donor" pads (i.e. either new or used so that the backing plates can be used). Carbotech charges $599 for the front pad set (i.e. eight pads), and $139 for the rears (i.e. four pads).

Contact Info:

Carbotech USA, Inc.
Speak with Matt or Larry
(877) 899-5024
(704) 481-8500
P.O. Box 2907/2407 South Post Road
Shelby, NC 28150

I believe that Carbotech also makes a XP1109 (XP9) compound. However, these pads are less streetable (i.e. they make more noise, and have a higher cold bite-point, temperature-wise). Besides having a higher cF, they also have a higher fade threshold due to the fact that they have a higher maximum operating temperature. Carbotech does not recommend using these pads on the street.

 

I recommend them as well but they are way too expensive. For $200 less for a set of front pads, Porterfield R4-S pads will also provide a similar improvement. Porterfield also has backing plates, so no cores are needed. The R4 pads I use are great but are very noisy and dusty. The street compound is more appropriate if not using the car on the track. If the wear sensors are disconnected, no warning appears on the dash, as I run without them.

Hey Eliot, how do you like your ride. Any track days planned?