Skip advert
Advertisement

Mercedes-AMG GT S breaks 205mph with unofficial tuning kit

Over 600bhp from Mercedes' sports coupe with latest performance tuning

While some might decry the move towards turbocharging and ever more electronic control in modern performance cars, there’s little doubt it’s made tuning more accessible than ever.

Nowhere is this more evident than in the highest performance vehicles. German firm performmaster has turned its attention to one of the best – the Mercedes-AMG GT S – and the result has lifted its top speed to 205mph.

Advertisement - Article continues below

Available for both the GT and the GT S, the PEC tuning module can be installed alongside the standard ECU with three OEM plugs, eliminating the need to hack into cables and ensuring the car can be returned to its standard output at any time.

That output increases from 456bhp in the GT and 503bhp in the GT S, to 603bhp from either car. As a result, the standard 189mph and 193mph top speeds are lifted to 205mph.

Acceleration also improves by a healthy margin, dropping the 0-62mph sprint from 4sec in the GT and 3.8sec in the GT S, to 3.6sec. Up to 124mph from rest, the difference is even greater – the tuned model cuts 1.3 seconds from the GT S’s 11.5sec figure.

Similar performance will soon be available in the Mercedes-AMG C63 saloon and estate, too – since both use the same 4-litre, twin-turbocharged ‘hot V’ as the range-topping coupes. Peace of mind for owners comes in the form of a 24-month or 100,000km (62,137 mile) warranty for the entire engine and transmission.

As further example of what simple electronics tuning can achieve, performmaster notes that other packages can take the A45 AMG (and similarly-engined models) to 405bhp – greater even than Mercedes’ own revised A45 – and the CLS 63, E 63 and S 63 AMGs to a healthy 692bhp.

Skip advert
Advertisement

Recommended

Mercedes-AMG GT review – better than the original, but a match for the Porsche 911?
Mercedes AMG GT 55
In-depth reviews

Mercedes-AMG GT review – better than the original, but a match for the Porsche 911?

A sophisticated new chassis, up to 805bhp and a more practical cabin provide the Mercedes-AMG GT with everything it needs to take on the best in the b…
13 Apr 2026
Skip advert
Advertisement

Most Popular

Lotus wants to save its Norfolk factory by developing and building other company's sports cars
Lotus factory
Features

Lotus wants to save its Norfolk factory by developing and building other company's sports cars

The Emira will live on and there's an Esprit supercar on the way, but Lotus has another plan to keep Hethel active
18 Aug 2026
Ford Focus RS (Mk3, 2016 - 2018) review – the last proper fast Ford?
Ford Focus RS
In-depth reviews

Ford Focus RS (Mk3, 2016 - 2018) review – the last proper fast Ford?

The Mk3 Focus RS looks like it’ll be Ford’s last RS, certainly with petrol-only power, for a while if not ever. Did the legendary badge go out on a hi…
18 Aug 2026
BMW i3 Touring spied – will this be the most desirable daily EV?
BMW i3 Touring
News

BMW i3 Touring spied – will this be the most desirable daily EV?

BMW will expand its i3 offering in all the usual ways it does with the 3-series. The upcoming Touring has been spied testing with a thin disguise
19 Aug 2026