My first thought was "just buy a 211." Didn't post that up because I didn't want to rain on anyone's parade, but it looks like I'm in the comfortable majority. The mods are a lot of money to spend on a 210 E55, and you won't get any of it back when you sell the car - it's 100% sunk cost.

I've driven everything - 124.036, 210 E55, 211 E55, 211 E63, 212 E63 - and the 211 E55 really stands out if you want brute power. It is nothing like the naturally aspirated cars. It's unrefined in comparison, it's brutal, it makes huge amounts of power right from idle. I think of it as a muscle car more than a sports sedan.

The driving feel of a 211 is not all that different from a 210. No big surprise, the cars are not that different - similar size, similar weight, similar suspension design. If you like a 210, you won't be disappointed with a 211. Steering is light but accurate. Absolute grip is quite good, though of course dynamics are a challenge on such a large, heavy sedan.

I don't know that ownership costs on a 211 are all that much higher than a 210. The SBC brakes have a 10 year warranty, so that's covered. The 722.6 trans is going to be about the same cost. The 5.4 liter V8 is substantially the same. So the main differences seem to be the supercharger and air suspension.

Airmatic ain't that bad. There is a reliable strut rebuilder for $400, and they are easy to replace. The pump doesn't go bad unless you ignore a leak too long. And it does offer a more impressive ride/handling compromise than any coil sprung car I've spent time in.

Superchargers are pretty reliable, if not infallible. But hey, look at all the window regulators you won't have to replace.

BTW, rotors on a 211 E55 are only about $100 each. The E63 went to a 2 piece rotor, and it costs almost 10 times as much.

I don't think you're going to get near 100HP/liter out of a naturally aspirated 3-valve, SOHC motor.

OK, this has been more than a bit rambling, but isn't meant to be a sales pitch for a 211. Rather, if you can be happy with the 210 without dropping a bunch of coin on it, then it makes sense. But if you got to have a bunch more performance, I feel you are better off just going for a 211. They're not that scary - I have one!

- JimY