Although the performance figures look good on paper, Mercedes-AMG customers are not interested in buying the AMG C 63 and GLC 63 models equipped with the PHEV system based on a 4-cylinder internal combustion engine. For this reason, Mercedes-AMG is working on a new V8 engine for the AMG 63 models.
In the modern Mercedes-AMG model lineup, the number 53 is associated with a 6-cylinder inline engine, while the number 63 is associated with the 4.0-liter twin-turbo V8.
However, due to increasingly strict emissions regulations, Mercedes attempted to heavily electrify the top AMG versions of the C-Class and GLC ranges. This was successful only on paper, as the performance of the new PHEV system based on a 4-cylinder engine is indeed impressive: up to 680 PS and 1,020 Nm. These figures easily surpass those of a V8, but customers are not interested, which is why few AMG C 63 and AMG GLC 63 units have been sold.
Since the new Mercedes CLE coupe is built on the same platform as the C-Class, early rumors suggested that the top version, the AMG CLE 63, would inherit the PHEV system from the Mercedes-AMG C 63 S E Performance, which is based on a 4-cylinder engine.
However, it now seems that Mercedes has dropped this idea. In the case of the CLE, the lower-tier version, the AMG CLE 53 4Matic, already comes with a 3.0-liter inline 6-cylinder engine producing 449 PS, as part of a 48V mild hybrid system that also includes a 23 PS starter-alternator.
According to information provided by the British magazine Autocar, citing former top AMG executives, the AMG CLE 53 4Matic, which is a very well-received model, will remain the top version for a longer time, as AMG has decided to change its strategy.
AMG has decided not to equip the top version AMG CLE 63 with the 4-cylinder PHEV system, but instead to use a new V8 engine. This engine is not entirely new but rather a development of the current M177, which will receive a 48V mild hybrid system with an integrated starter producing around 20 PS. As such, this engine could deliver 585+20 PS or 612+20 PS.
AMG boss Michael Schiebe once stated that there would no longer be V8 engines in the AMG C 63 or AMG E 63, but that AMG would still use the V8 in other models. When asked by Auto Motor und Sport whether the V8 engine could find its way under the hood of the AMG CLE 63, Schiebe said he would not comment on future possible models or speculations.