Here are 3 of my posts from other threads
My previous C55 ran on Conti Sports and an open diff, changed to Michi Pilots and it changed things, I then added the Quaife, which helped again.
It wasn't a radical change whereby I gained 50% grip more a case of 10/20% more off the line in the wet, a lot better under braking.
High powered RWD and cold, damp or wet roads is always going to be the compromise.
I had P Zero's on my current car and didn't like the feed back, now on Michi Pilots and rate them, overall I rarely hear poor reports of Michi Pilots and I've used them on a few of my cars.
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My C55 was tricky to drive in poor weather, it was best exploited on a warn dry day, then, I had the LSD installed, it tied the rear and front together but still suffered in poor conditions. When I say tricky, not pushing on like an idiot more along the lines of pulling away at busy junctions, over taking from slower speeds, turn in on wet roads, normal every day driving.
It was biased as a fast road car NOT a track day weapon, on the roads it was fine to drive and you had to moderate your style to adapt to the conditions.
My replacement 996 turbo is 4WD and in all the above situations it requires little to no moderation to driving style, this could possibly be a combination of factors, chassis related rather than just the 4WD system.
Some have clearly purchased the 63 for the event, others to scratch an itch, it's a personal thing but there is no escaping the 63 is a handful and needs lots of moderation in anything other than normal weather conditions, I'm sure it's a real hoot in summer with the LSD.
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If you have a performance RWD car then the ATB should be one of the first modification made, I would never own another RWD AMG without one installed.
Big thank you to Paul for a great price and service and to PCS for there usual A1 customer care, I dropped my car off Tuesday morning and collected today, courtesy car was a nice touch.
I've driven plenty of cars with a Quaife installed so more or less knew what to expect, my C55 already has many modifications to enhance the handling, the coilovers are fantastic, C63/SLK55 brake upgrade, power delivery is as you expect with any V8 AMG and prior the Quaife I was very pleased with the way the car performed.
The diff has tied in the rear end, more feel, positive and progressive when you turn in on the throttle, very little intervention from the traction control, yes the light flickers but no intervention, I love the front end turn in with the coilovers but it always felt like the back end was a couple of steps behind, trying to catch up at it's own pace, now I can feel the synergy between front and back, very predictable.
Most comments I've read in this thread refer to the increased off the line traction, yes this has improved and enormous amount but for me the bigger story is how it has transformed the balance of the car, as expected, one of the best modifications made to the car.
