Originally Posted by California John

Nice writeup!

I have some questions:

1) Can you please comment on the wind turbulence in the R232 SL with the top down, windows raised, the wind deflector fit in place, and cruising at 70+ mph?
--> I am wondering if you could put the wind turbulence performance in context - would you be able to compare it to that of the R231 SL (probably the best convertible ever made for minimal wind turbulence), the Porsche 911 992/992 (excellent wind turbulence performance but not quite perfect like the R231), or other modern convertibles?

2) Can you compare the presence of body roll in the R232 (I observe that yours has active ride control with roll stabilization) with, say, any other SL generation car which had ABC which you have driven/owned?

3) Mercedes has a desire to go after Porsche and the 911 with this car. That seems very silly to me when the R232 SL is some 900 pounds heavier as well as 7-8 inches longer. In any event - have you owned a 991 or 991 cabriolet with which you might compare agility and overall sports car feel?

4) There has been talk of a wind noise issue with the top up, drive side window, forward near top of window. Can you comment?

5) With the top up and windows raised — or in coupe form with windows raised — Porsche 911s in general exhibit substantial road noise and roar at highway speeds. Interior ambiance is not very quiet. With the top up and windows raised in the R232 SL, can you comment on how it compares?

6) Any chance you could compare the experience in the R232 SL with that of the BMW M850i convertible?[


1) I had an R231 a number of years ago. I haven't noticed any more turbulence than that. I have no experience with the Porsches. I haven't driven my new one with the top down and windows up with the wind deflector. With the windows down - yes. Quieter than without the deflector at higher speeds.

2) My previous SL R231 had ABC. This new one is a totally different ride. Not rougher at all but more stable and "together" at speed. Definitely better turn in and more precise. While the ABC kept the previous version level, it was not crisp compared to the new one.

3) No experience with the Porsches.

4) There is some wind noise with this soft top up. Doesn't bother me...but I expect some noise when it's a soft top convertible. And....I almost always have the top down.

5) No experience with the Porsches.

6) Sorry no experience with the BMW.

Originally Posted by Wolfman

The GTC and GTR have the same M178 engine and feature larger turbos vs the GT or GTS. These all have dry sump lubrication.
The SL63 has the M177 engine like the E63s. The question here is wether the turbos are single or twin scroll. The power is a little low for the twin scroll or maybe it's just detuned (577hp vs. 612hp).

Originally Posted by RafLimeRock

I owned a GT C for nearly 6 years. I sold it in favor of the SL63. The GT C was fast but not fast enough so I installed the Renntech ECU upgrade. This brought the car to life. My impression is that the SL63 is far stronger than the 585 HP advertised. It is certainly torquier and faster than a standard GT C and I am not sure that it is much slower than my GT C after the Renntech upgrade. According to Renntech, AMG power ratings are woefully inaccurate and underrated. My early seat of the pants experience confirms this and it may be because my GT C being rear-wheel drive, delivered real power when already at “town“ speeds. The advantage of the SL is that the car puts the power to the road brilliantly. The draw back of the SL is that it is heavier, but AMG have done a great job in masking the weight as the car is teutonically agile especially when driving in anger. It is obviously not a track car but it is an outstanding all rounder and there aren’t many cars on the market that have the breadth of ability of the SL. I will need to own the SL for more time to decide whether to upgrade with Renntech power but the fact that I am not in a hurry to do so is because the breadth of the SL’s ability can not be explored by short term ownership or a review test drive. In my opinion some car reviews judge the car by the wrong criteria. A cross shopper would consider a Bentley GTC, a Ferrari California, or a BMW M8 convertible and possibly a Porsche GTS convertible. All these cars are excellent choices and the right choice in the eye of the beholder. I enjoy new technology and the SL provides plenty, which is why it was a good choice for me. When I am in the mood to drive a drivers car I get into my Lotus Evora GT, which is uncompromising, low tech and an exquisit experience.

Originally Posted by RafLimeRock

I owned a GT C for nearly 6 years. I sold it in favor of the SL63. The GT C was fast but not fast enough so I installed the Renntech ECU upgrade. This brought the car to life. My impression is that the SL63 is far stronger than the 585 HP advertised. It is certainly torquier and faster than a standard GT C and I am not sure that it is much slower than my GT C after the Renntech upgrade. According to Renntech, AMG power ratings are woefully inaccurate and underrated. My early seat of the pants experience confirms this and it may be because my GT C being rear-wheel drive, delivered real power when already at “town“ speeds. The advantage of the SL is that the car puts the power to the road brilliantly. The draw back of the SL is that it is heavier, but AMG have done a great job in masking the weight as the car is teutonically agile especially when driving in anger. It is obviously not a track car but it is an outstanding all rounder and there aren’t many cars on the market that have the breadth of ability of the SL. I will need to own the SL for more time to decide whether to upgrade with Renntech power but the fact that I am not in a hurry to do so is because the breadth of the SL’s ability can not be explored by short term ownership or a review test drive. In my opinion some car reviews judge the car by the wrong criteria. A cross shopper would consider a Bentley GTC, a Ferrari California, or a BMW M8 convertible and possibly a Porsche GTS convertible. All these cars are excellent choices and the right choice in the eye of the beholder. I enjoy new technology and the SL provides plenty, which is why it was a good choice for me. When I am in the mood to drive a drivers car I get into my Lotus Evora GT, which is uncompromising, low tech and an exquisit experience.

Originally Posted by JohnGigi

I'm inclined to agree on the timing for the Renntech and since I am putting about 15,000 miles a year on my 63, I won't be in full warranty that long anyway. Unfortunately, according to my Renntech response I would have to go to Dallas to get it done. Was raised there, but hate the traffic now compared to the Hill Country.

Any experience with MB getting pissy about the modification? Chevrolet didn't care about similar upgrades. I've left my M8 alone.

Originally Posted by JohnGigi

Sure. Just to clarify, are you saying that this is a MB dealership that does the Renntech instalation?