Just before Christmas I drove a CLS 55 AMG and was very impressed with the traction and grip offered by the 285/30/19 rear tyres. Better still, the ride comfort and tyre noise levels with Airmatic suspension were actually very good.
I got to wondering if this rear tyre section would work on the S Class.
Six weeks later some Kahn RS-X Diamond Edition wheels popped up on ebay with 21” rears and 20” fronts. These would give the same overall diameters as the staggered AMG 20” option for the S class with 285/30/21 rears. I put in a silly offer and to my surprise it was accepted! I guess the odd sizes put most people off, but I saw this as a positive advantage being able to maintain a similar 3” gap from rim to road both front and rear. I’ve run many cars with different front and rear wheel sizes and even raced some with different compounds on each corner! The tyre profiles with 255/35/20 fronts are incidentally the same as those chosen for the latest M5 beating Jaguar XFR.
Tyres were carefully selected from those I have personal experience with, Conti SportContact 2 rears and Dunlop SP 01 fronts. Price and availability are also issues with the rear size being like hen’s teeth. Both are non directional so I can at least swap side to side. Some of the more aggressive directional treads (GSD 3, Sessanta and Falken 452) have quite high rolling resistances.
The Conti’s I knew had good grip and wear characteristics but can become noisy when worn. It happens with all tyres, but some more than others, and is due to the tyre ‘ringing’ or resonating more as the fat tread damping ‘belt’ reduces in mass. It’s very noticeable on concrete road surfaces. The Dunlops I already have on 19” wheels and are good all rounders. (Pun intended!)
The centre caps are normal Mercedes chrome star ones, but I’ve taken them apart and covered the cap in metallic titanium vinyl to match the wheel colour before bonding the chrome stars back on.
I’m very pleased with the result; the grip and particularly the traction is much better. Ideal for putting down over 600Nm of torque. While I will not claim to have improved the ride or interior noise levels, they have remained perfectly acceptable thanks to the Airmatic. Still a little better than the CLS on 18” wheels that I have been in this week.
It’s too early to say if the fuel economy has suffered, but I’m expecting a 1 or 2 mpg hit.
The looks of the car are now a bit Marmite. You either think ‘purposeful’ or ‘bling’. If you think the wheels look a bit ‘drug dealer’ then that’s probably because their previous owner was a….pharmacist! You couldn’t make it up!
I got to wondering if this rear tyre section would work on the S Class.
Six weeks later some Kahn RS-X Diamond Edition wheels popped up on ebay with 21” rears and 20” fronts. These would give the same overall diameters as the staggered AMG 20” option for the S class with 285/30/21 rears. I put in a silly offer and to my surprise it was accepted! I guess the odd sizes put most people off, but I saw this as a positive advantage being able to maintain a similar 3” gap from rim to road both front and rear. I’ve run many cars with different front and rear wheel sizes and even raced some with different compounds on each corner! The tyre profiles with 255/35/20 fronts are incidentally the same as those chosen for the latest M5 beating Jaguar XFR.
Tyres were carefully selected from those I have personal experience with, Conti SportContact 2 rears and Dunlop SP 01 fronts. Price and availability are also issues with the rear size being like hen’s teeth. Both are non directional so I can at least swap side to side. Some of the more aggressive directional treads (GSD 3, Sessanta and Falken 452) have quite high rolling resistances.
The Conti’s I knew had good grip and wear characteristics but can become noisy when worn. It happens with all tyres, but some more than others, and is due to the tyre ‘ringing’ or resonating more as the fat tread damping ‘belt’ reduces in mass. It’s very noticeable on concrete road surfaces. The Dunlops I already have on 19” wheels and are good all rounders. (Pun intended!)
The centre caps are normal Mercedes chrome star ones, but I’ve taken them apart and covered the cap in metallic titanium vinyl to match the wheel colour before bonding the chrome stars back on.
I’m very pleased with the result; the grip and particularly the traction is much better. Ideal for putting down over 600Nm of torque. While I will not claim to have improved the ride or interior noise levels, they have remained perfectly acceptable thanks to the Airmatic. Still a little better than the CLS on 18” wheels that I have been in this week.
It’s too early to say if the fuel economy has suffered, but I’m expecting a 1 or 2 mpg hit.
The looks of the car are now a bit Marmite. You either think ‘purposeful’ or ‘bling’. If you think the wheels look a bit ‘drug dealer’ then that’s probably because their previous owner was a….pharmacist! You couldn’t make it up!
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