Both the GLC 43 and GLC 63 now feature highly-tuned 4-cylinder engines, replacing the previous V6 and V8 units.
The GLC 43 develops 415bhp, while the hybrid powertrain in the GLC 63 has 469bhp on tap, making it the most powerful series-produced 4-cylinder engine in the world.
A boost mode on the GLC 63 uses an AMG electric drive on the rear axle to increase power to more than 641bhp for bursts of up to 10 seconds.
As such, the GLC 63 is capable of 0 to 62mph in 3.5 seconds with a top speed of 171mph, yet the hybrid system enables it to return up to 37.7mpg.
The GLC 43 is not quite as quick, with a 4.8 seconds 0 to 62mph acceleration time and a maximum limited to 155mph.
Both are fitted with 9-speed automatic transmissions and, compared to a standard GLC, the performance pair have their own suspension systems with adaptive dampers.
Exact prices and full specification are still to be revealed, and the cars will be available either later this year or early in 2024 with the GLC 43 expected to cost around £70,000 and the GLC 63 more than £100,000.
On a practical front, luggage space on the GLC 43 is a generous 620 litres with a maximum of 1,680 litres while the hybrid set up on the GLC 63 reduces space to 470 litres with a maximum of 1,530.
Prices correct as of 18/07/23 and are subject to change.
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