ENGINE 3982cc V8, DOHC, 32v, twin-turbo / POWER 410kW @ 6750rpm / TORQUE 680Nm @ 1900rpm / WEIGHT 1660KG / 0-100KM/H 3.7sec (claimed) / PRICE $330K (est) R ULES are made to be broken at AMG. The latest rule theyíve broken is the one that says any car will be worse when you cut the roof off it.
Bound to be, usually, because the roof is an integral part of the chassis and itíll never quite be the same after you light up the gas axe, even if you bolt an I-beam underneath it.
But AMG cut the roof off the GT C coupe and created a roadster that almost matches its progenitor in every tangible way, but surpasses it by every visceral measure.
The GT Cís abilities were well beyond most drivers anyway, and AMG has dialled that back a touch and used that grip reserve to ratchet up the emotions without losing its integrity. It ends up being more of a sports car, more of the time.
You can tell almost instantly that itís beautifully organised and R integrated below decks, in part down to floor-level scaffolding and in part due to AMG sticking in more ďcell blocksĒ in the thicker aluminium sills. The Z-fold roof system is brilliant in the real world, rising or falling in 11 seconds and doing either at up to 50km/h.
Its chassis feels rock solid and its suspension complements it, and that thumping 410kW version of the dry-sump 4.0-litre hot-vee twinturbo V8 is always either burbling or bellowing.
Itís a car that exudes confidence in everything it does and it osmoses that confidence into its driver, so much so you quickly begin to throw it into corners well beyond its grip limits, safe in the knowledge that the car beneath is faithful and fun as well as fast.
The rear-driver gets a big dose of handling help in the form of the GT Rís rear-wheel steering and itís just a charming place to be whether the carís pushing along at two of its tenths or 10.
It goes from gentle cruises full of birdsongs with the roof down to fully-fledged fauna frightener, brimming with turbo fizzes, pump whines, exhaust bellows, pops and crackles, in the flick of an ankle.
You donít smile just because of the power and torque, though. You smile because it has enormous breadth of character, capable of driving with the roof down at up to 160km/h before any significant buffeting begins and voices need to be raised.
Itís about 50kg heavier than the Coupe, at 1660kg (DIN), but its only significant shortcoming is a 65-litre tank, which Iíd personally feel compelled to empty every time I saw the needle on full.
Thereís a base version of this car that detunes the twin-turbo V8 down to 350kW, but why bother with
Engine; dynamics; looks; noise; theatre
Weighty beast; small fuel tank
that when the GT C boasts 26kW more than the GT S Coupe and falls just 20kW shy of the Nurburgringeating GT R? It's a power haus.
Itís not all about power, though.
That helps when you want to snap to 100km/h in 3.7 seconds and on to 316km/h. Power is the headline, while the 680Nm of torque between 1900 and 5750rpm is what gets the job done most of the time for most people. Feeling flexible and potent at the same time.
It has no weak points in its range, working like an ox at 2000rpm, snapping out of a corner at 4500rpm or screaming up to 7000rpm before a gear change. And you can hear more of the engineís heavy breathing with the roof off.
The GT C also stretches the rear end 57mm wider to accommodate the 305/30 R20 rear rubber, takes in an electronically-controlled locking differential (the standard car uses a mechanical unit), gains adaptive damping, a stronger seven-speed dual-clutch transmission, it uses the loudest exhaust system, tarmactearing brakes and it even has a Race mode. In other words, it's well equipped for this stuff.
You can fling it at corners carrying ludicrously exaggerated speed and it will begin to push at the front before the rear steering and the differential join the party and calmly, seamlessly ease it all back into line.
Itís the same when the tail begins to slide. The body control is brilliant, too, and it rides bumps sensationally well, whether itís cruising or loaded up mid-corner.
Mercedes-Benz Oz last told us the car's due to arrive in the third quarter this year. And it will be then followed by the coupe version and updated GT in early 2018.
So you can pencilt that in for a showdown with Porsche's 911 GTS.
This is one of the easiest junior supercars weíve ever had to live with, and itís somehow softer and more charming, all the time. M