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 – front
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 AMG GT with everything it needs to take on the best in the business
9 Jan 2026
Mercedes AMG GT Track Sport testing – special with GT3 RS-rivaling road potential shapes up
Mercedes Concept AMG GT Track Sport
News

Mercedes AMG GT Track Sport testing – special with GT3 RS-rivaling road potential shapes up

Mercedes-AMG has skipped right past any new GT R or black series to a track-spec race car for the road. We hope it makes production…
28 Oct 2025
Skip advert
Advertisement

Most Popular

Peugeot’s new petrol engine swaps belts for chains to improve reliability
Peugeot Turbo 100
News

Peugeot’s new petrol engine swaps belts for chains to improve reliability

New engine isn’t performance-oriented but does address some reliability issues around so-called ‘wet belts’, swapping them out altogether for chains
16 Mar 2026
The new Jaguar GT is lovely to drive, but that’s not enough for people to buy it
Jaguar GT
Opinion

The new Jaguar GT is lovely to drive, but that’s not enough for people to buy it

The Jaguar GT has the hallmarks of a deeply impressive luxury saloon. Whether it can turn the tide on slow demand for premium EVs is another matter
11 Mar 2026
Audi Q3 review – polished BMW X1 rival available with Golf GTI power
Audi Q3 review
In-depth reviews

Audi Q3 review – polished BMW X1 rival available with Golf GTI power

The Q3 confounded some of our middling expectations for it. This is a pleasant, neat-driving small SUV, albeit with a few flaws and catches
13 Mar 2026