Watching the speedo nudge 240kmh on a brief straight section of single track Spanish tarmac between some excellent snakey bits felt a bit silly yesterday, and it did make we wonder where this whole thing is going to end. In prison, probably.
But it's not philosophical, cultural or even legal issues that are potentially slowing Herr Poggel's progress - it's heat build-up. Apparently, reducing capacity (the last M5 had a 5.0 V10) and adding turbos to (over?) compensate for the loss makes a lot more of the stuff, and getting it out of the car is a bit of a problem. Still, that's what these guys are paid for, and they'll probably think of something...
Nestling is probably a better word than lurking, as despite their size the twin turbos have been dropped neatly between the vee of the engine - as per the installation in the X6 M - which is to all intents and purposes the same engine. Herr Poggel says changes are limited to the M5's Valvetronic system, bigger intakes, bigger turbos and an oil system that has been 'race-prepped' to withstand Nurburgring Taxi duties, and other possible abuses.
Which is how you get 560hp and 502lb ft out of a 4.4-litre V8, while making your new business express a whole 30 per cent more economical than its predecessor on the combined EU cycle. Amazing stuff, eh?
Wringing the nuts off the old 8,250rpm-limited V10 was a rewarding pastime, but it's less so with the new V8. Peak power arrives at 6,000rpm and is maintained at a plateau until just before the limiter comes in at 7,200rpm - which is impressive, but leaves you with a distinct feeling that not shifting before 6k was a bit of an oversight. There's a nice V8 engine note, but just a little too muffled for my tastes, which is probably the fault of those turbos again. (And I have spent the last 20k miles in an AMG C63...)
On the road, the performance is just mind-boggling. With a super-smooth 7-speed twin-clutch robot manual gearbox similar to that in the M3, you can grab a couple of gears with the left hand paddle while you floor it, and your overtake will be over pretty much the moment you thought of it. It's too fast to contemplate, really and, without an unrestricted autobahn to play on, definitely a potential licence loser.
The chassis, while undoubtedly a marvel of balance and poise, rides rather softly and even in Sport+ damping mode (adjustable, along with the engine response and steering via the M set-up menu), the car remains relatively soft.
The steering too, hydraulic instead of the 5 series' horrible electric option, is direct and accurate but lacks that finger-tip incisiveness of - say - recent Jaguars. All in all, it's as though BMW has taken an executive express and given it super-hero powers, but without that added dash of 'darkness' that used to give this sort of car so much of its personality.
So what we're left with is a technological tour-de-force, certainly, but will this iteration of the M5 recipe resonate across the decades as other M5s have before it? Time will tell, but if you're into the business of going properly fast and in comfort, I'd be amazed if there's another big saloon out there to touch it.