You get the overriding impression that both the BMW 1 Series M Coupé (from now on referred to as just the 1 M) and Porsche's Cayman R kind of slipped through the net. They're clearly the product of BMW and Porsche's skunk-works departments, after-hours projects driven by hard-core enthusiasts building the cars they want, rather than models designed to fulfil a product manager's brief.
That the 1 M exists at all is surprising, especially as it effectively does everything its big brother, the M3, does but at a more affordable price. Given that the older sibling is effectively in its twilight years, someone, somewhere, surprisingly gave this M division machine a nod for production. Initially it was to be a limited-run model, but such is the interest it's rumoured that BMW has lifted the cap on production and will build as many as it can before the 1 Series Coupé it's based on is replaced in 2013.
The Cayman R is the car that Porsche's customers have been asking for since the original was introduced. At the press launch, Walter Rohrl himself quipped that a lighter Cayman R with a limited slip differential was as quick if not quicker than a contemporary 911. That was back in 2005, Porsche never a firm to rush into things. It's typically Porsche, too, in that it's incremental, rather than seismic, changes that have created it; the end result gelling in a whole that's infinitely greater than the sum of its parts.
That both cars represent a more bombastic yet intimate driving experience cannot be denied, but what's fascinating is the differences, despite the obviously shared goals. BMW's M division has taken a 1 Series Coupé, fitted a 3.0L straight-six with second generation "Twinpower" turbocharging and direct injection to boost output to 340hp. Torque of 450Nm (plus 50Nm on overboost) from just 1,500rpm right up to 4,500rpm creates a 1 Series that's able to cover the 0 to 100kph sprint in just 4.9 seconds.
The Cayman R trails that, its mid-mounted 3.4L flat-six (the BMW is front engined) giving up 20hp to the BMW, with 320hp on offer. Naturally aspirated rather than assisted by turbocharging, the Porsche's 370Nm of torque isn't quite in the BMW's league, and neither is it so accessible - that peak torque arriving at a relatively high 4,750rpm. That results in a 0 to 100kph time of 5.0 seconds - a number that can be dropped to a 1 M-matching 4.9 seconds if you specify your Cayman R with Porsche's paddle-shifted PDK transmission.
To do so would be to miss the point though, as both the Cayman R and 1 M are meant to be driven - and that means changing gears manually. It's to be applauded that the 1 M is only offered as a manual and, if you're interested in a paddle-shifted Cayman, just buy an S and be done with it. Both are cars where you can enjoy rolling your foot from the brake and blipping the throttle to match engine revs to road speed and slip in another gear.
The action of the shift in both is familiar, the 1 M's retaining the slick springiness of its M3 sibling; quick but perhaps lacking that mechanical precision that marks out the shift in the Cayman R. If you've never used a Porsche manual gearbox, you're missing one of the few remaining intimate man-machine interfaces in the automotive world. You can feel the gears meshing as the lever moves though the gate, the light clutch allowing you to jab though ratios swiftly, or languidly push the stick through and enjoy the feel. The BMW's shift is good, but a poor relation to that in the Cayman R.