Road test: Mercedes-Benz AMG GT S

The SLS's successor can take on the Porsche 911. We take the machine for a spin.

The Mercedes-Benz AMG GT S is a less-exclusive heir to the SLS, with its power down by more than 150hp. Courtesy Mercedes-Benz

First impressions are made at lightning speed. Some suggest that there’s a part of the brain hardwired to its prehistoric survival mechanism that instantly triggers the kind of fight-or-flight warnings that have kept us off the menu of larger and superior predators.

We’re able to complete a series of complex calculations in a matter of seconds; run through various scenarios in our heads and settle on major decisions at an alarming rate. We, as humans, have nailed that down to under seven seconds. In that time, we’ve already worked out how we’re going to deal with something or someone new pretty much for life.

These snap decisions now guide us through the challenges of everyday life in the 21st century. For some, that’s hiring a new staff member. For others, it’s deciding whether they’re going to park a new Porsche 911 in the driveway or take a punt on the new Mercedes-Benz AMG GT S.

Borne out of the discontinued SLS, the AMG GT S is the second car developed entirely in-house by the ­Affalterbach-based Mercedes-AMG. Like the SLS, the GT S is a halo car that sits at the top of the company’s performance ladder, but unlike the exclusive SLS – and editions like the sublime Black Series that pushed a seven-figure sticker price – the AMG GT S doesn’t carry anywhere near the same kind of premium.

By bringing its halo car downmarket, Mercedes is declaring open season on cars such as the 911 and Jaguar F-Type R coupé. After a day throwing the car round California’s country roads and the Laguna Seca Raceway, it’s clear that the AMG GT S will cause both a few ­headaches.

One of the reasons for this is, for a sports car, the AMG GT S is all things to everyone. The twin-­turbo, 4.0L V8 may lack the outright displacement of the 662hp, 6.2L, naturally ­aspirated engine that AMG bolted into the front of the SLS, but it still delivers its 510hp with a punch that will focus your mind on the job at hand. The car will hit 100kph from standing in 3.8 seconds, and won’t stop accelerating ­until 305kph, yet it will do so with such ease that you really wonder whether the digits on the speedo are reading correctly.

To justify AMG’s “handcrafted by racers” boast, they went back to the drawing board in 2011. The chassis and bodywork was a clean-sheet design that took its inspiration from the success of the SLS. Engineers cut nearly a foot out of the wheelbase of the SLS, shortened the overhangs at the front and rear, and redesigned the chassis and most of the body panels to be made out of high-strength aluminium. The boot hatch is made from steel because its complex shape would have required so much aluminium to provide enough strength that it would have weighed more than steel and reduced the rear window to a mail-slot-sized slit.

Its engineers also dipped into its race-car trick bag with the drivetrain. The engine’s dry-sump lubricating system and the hot-V turbo layout (they sit in the V of the engine to cut turbo lag and emissions) means the engine can be mounted lower and farther back in the chassis. Drive is fed to the rear transaxle, the seven-speed transmission is fed by a carbon-fibre propshaft, while a set of dynamic chassis mounts means the GT S can be tuned for a comfortable road ride or ballistic track driving with the quick turn of a dial.

Laguna Seca may only have 11 turns, but they’re all extremely important to nail for a decent time – and the AMG GT S turns in some fairly flattering laps. With the two-time German touring car champion and Dubai 24-hour endurance racer Bernd Schneider up ahead in a lurid green, ­tiger-striped AMG GT S (a ­factory-option livery, ­apparently), I’m working hard to stick to his tail. Race mode is dialled in – given the slightly damp conditions, it’s a bit of a concern as we blast over the blind crest on the pit straight at well north of 190kph and wait for the car to settle before standing on the brakes to slow for the Andretti hairpin.

The car turns in well, there’s plenty of front-end grip that begins to fade as you plant the throttle, and the car builds speed as quickly as you can reach for another gear. The Corkscrew is difficult to master, particularly when you’ve got a long bonnet and low roofline restricting the view ahead, but the plunge down the hill through Rainey Curve at more than 120kph, with the AMG GT S delivering the full scope of its 510hp, is spectacular.

Whether the AMG GT S will take lumps out of the 911’s showroom statistics remains to be seen, but news that a non-S variant is due later this year and the fact that AMG is developing a GT3 race car and a hot road version, can’t have gone down terribly well with Porsche.

For those in the enviable position of being able to choose between the two, the AMG GT S doesn’t disappoint.