I've had the MSL Stage 1 remap on my C63 (W205) for a week (I thought the group buy was taking too long, so paid full price) and I'm over the moon with it, this is the third C63 that I've owned, previously two W204's and all of them had an MSL remap.
The W204 and W205 are both electronically limited, in the case of the W204 C63 it was electronically limited by Mercedes in order that it wasn't faster than the E63, so a remap simply allowed it to produce what it was designed too, by opening the throttle bodies fully and mapping the fuelling to match, the car was then put on the rolling road at MSL and final tweeks were made to optimised and ensure the fuelling was correct through the entire rpm range and load input. It totally transformed the capabilities of the car, but maintained it's road manners, if you wanted to drive in comfort mode, it still had the extra power available should you wish to use it, but if you wanted to drive sedately it would do that too, it's all down to the input you, the driver puts in.
My new W205 C63 engine is again limited electronically as the same engine is fitted in the AMG GT producing around 580bhp, so MSL Stage 1 map allows the engine to produce the same (At least). Mine has now been treated to a stage 1 remap which I downloaded onto my car via the MyGenius, and will have the final tweaks done when I get the chance, the new map is deliberatly mapped on the safe side, so I'm totally happy loosing a few bhp to ensure the engine is safe. However the difference it makes on the W205 C63 is low and mid range power, absolutely amazing and it's like driving a difference car, and the difference in available power is instantly noticable. But should you want to drive sedately it does this just the same as it would as standard, again it's all down to driver input. I would certainly agree with MSL's claims that this map allows the engine to produce well in access of 580bhp, but for me the torque is the most noticable difference, it just pulls so early in the rpm range, I've been in an Audi R8 V10 and I honestly believe that on a rolling start, the C63 is as fast, certainly capable of doing a 0 - 60 in sub 4 seconds, but it's the mid range acceleration that is the most noticable.
As i mentioned, i've had three C63's mapped by MSL and can assure you that you won't be dissapointed, and your car will perform how you want it too, but with more power should you need it.
Enjoy................... Here's Mine
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