V8 · twin-turbo
V8
AMG GTC sound: the GT C Roadster V8
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5 more Mercedes-AMG GT C Roadster sounds and Drive mode are in the free app.
Unlock all sounds freeThe Mercedes-AMG GT C Roadster sounds deep and aggressive, with a hard-edged V8 bark and loud crackles on the overrun, because its 4.0-liter twin-turbo M178 V8 breathes through a flap-controlled exhaust and, with the roof down, nothing stands between you and the noise. The start, idle, rev and drive recordings below come from the Car Sounds app.
What to listen for
- Start: the sharp flare to a high idle with the flaps open, then the drop into a steady burble.
- Idle: a deep, slightly uneven V8 beat, smoothed by the turbos but still unmistakably cross-plane.
- Revs: a hard, rising bark followed by a burst of crackles as the throttle snaps shut.
- Drive: the full midrange pull with a faint turbo whoosh and pops on every lift.
A front-mid V8 with turbos in the V
The GT C uses AMG's M178, a 4.0-liter V8 with both turbochargers mounted inside the V and dry-sump lubrication, which lets the engine sit low and far back behind the front axle. The gearbox lives at the rear axle, so the long hood is almost all engine.
Like the G 63's closely related M177, it has a cross-plane crank, so there is an uneven V8 burble underneath everything. The hot-V turbos take some edge off the pulses, which keeps the tone deep and full rather than raspy, while the short exhaust path keeps it crisp and responsive.
The exhaust flaps and the crackle
Most of the GT C's character comes from its exhaust. Flaps change the exhaust path depending on drive mode and load: in the calmer modes the car is fairly restrained, and in the sportier ones it opens up into a loud, hard bark. On the overrun, the engine's tuning adds the pops and crackles that many AMG owners chase.
The cold start is a big part of the appeal too. The engine flares to a high idle with the flaps open, then settles, which is why AMG GT cold start videos are a genre of their own.
Roadster vs. coupe
The GT C Roadster shares its engine with the GT C coupe, so the source of the sound is the same. The difference is what reaches you. With the soft top down, the exhaust, intake and every crackle arrive without a roof and rear glass in the way, so from the driver's seat the Roadster feels louder and more immediate.
Frequently asked questions
What engine is in the Mercedes-AMG GT C Roadster?
It uses the M178 4.0-liter twin-turbo V8 with the turbos inside the V and dry-sump lubrication. In the US it is rated at 550 hp.
Why does the AMG GT pop and crackle?
In its sportier drive modes the exhaust flaps open and the engine is tuned to produce pops and crackles on the overrun, when you lift off the throttle.
Is the GT C Roadster louder than the coupe?
The two share the same engine, so the sound at the source is the same. With the roof down, though, the Roadster lets far more exhaust and intake noise reach the cabin.
