BMW's M division knows how to put a fast car together, but even the experts there may be patting themselves on the back over the 2016 BMW M4 GTS. The latest creation from the famed tuners, the car billed as "the most agile, radical, and powerful M4 ever" was star of BMW's show at Amelia Island Concours d"Elegance this weekend, managing to hold its own against a variety of classic exotica (including more than a few models from BMW's own history books).
That's primarily because the M4 GTS isn't just a regular M4 with a bigger engine slotted in. Rather, the whole car has been reworked, with the goal of reducing curb weight, boosting power and - unexpectedly - even improving efficiency along the way.
The dramatic looks are courtesy of an aggressive body kit, with a carbon-fiber-reinforced plastic (CFRP) hood, roof, and adjustable front splitter. Aluminum shows up too, again for its reduced weight: altogether, BMW says the DIN curb weight is 3,329 pounds, a cut of around 200 pounds over the regular M4.
You notice it, too, just from opening the doors. Gone is the usual interior door trim, replaced with a spartan-but-lightweight panel with a fabric pull - in classic M Sport colors, naturally - rather than a hard handle.
Gone, too, is the rear bench seat, replaced with a simple glass-fiber reinforced plastic panel above which you see the Acid Orange of the roll cage that's made from high-strength steel. It color-matches the trim on the Alcantara-wrapped steering wheel and Alcantara-wrapped dashbord; the latter also gets a perforated "GTS" logo.
As for the seats, they're M Sports specials with cut-outs in the backrest to reduce mass, trimmed in black Merino leather with contrast stitching and Alcantara inserts. Safety fans will be pleased to see a fire extinguisher in there, too, though sadly BMW doesn't finish it in M Sport colors.
Outside, the most striking elements are probably the Acid Orange wheels with their contrast polishing. Made of forged aluminum, they're 19-inches on the front and 20-inches on the rear, with Sport Cup tires.
The brakes use carbon-ceramic ventilated discs, with 6-piston fixed calipers at the front and 4-piston at the rear.
BMW's 3.0-liter M TwinPower inline 6-cylinder engine gets a working over too, good for up to 493 horsepower and 443 lb-ft. of torque. Quoted top speed is 189.5 mph, with 0-60 mph in 3.5 seconds; you can either slam through the 7-speed M Double-clutch transmission via the steering wheel paddles yourself, or leave the gearbox to its own devices.
The really interesting part of the engine isn't even found under the hood, however. Open up the trunk and lift a hidden panel and you find a water injection system, fitted for the first time in an intercooled production car.
Basically, it injects a fine spray of water from a tank in the trunk into the intake manifold plenum chamber at around 10 bar. That evaporates, reducing the heat of the intake air in the process, and so the final compression temperature in the combustion chamber is also lower.
In turn, that cuts the chance of engine knock, allowing the 3.0-liter to run higher boost pressure and use earlier spark timing: power and torque get a kick up as a result, along with overall engine efficiency, and unlike many potency-improving technologies BMW claims this one actually cuts engine wear, rather than increasing it.
BMW says that, under regular driving conditions, you'll need to top the water tank up once every five tanks of gas. If you're pushing the M4 GTS on the track, though, expect to fill up at the same time as you fill the gas tank. Should you forget, or run out earlier than expected, the engine automatically operates as normal and you simply get a little less power.
Despite the pared-back interior, you still get a fair amount of technology. An 8.8-inch screen lives in the center stack, controlled with an iDrive knob, and there's adaptive cruise control, a head-up display, navigation, Bluetooth, and - important since you really, really don't want to scuff the orange spoiler lips - front and rear parking distance control.
BMW is offering four colors: Alpine White, Black Sapphire, Mineral Grey, or the matte-finish Frozen Grey of the Amelia Island car. No matter which you choose, you're getting a car that completed the famed Nüburgring in 7:28 mintes.
That is, assuming you got in early. BMW is only making 700 of the M4 GTS and, despite a sticker price that kicks off from $134,200 in the US, every single one has been sold.