Mercedes is consolidating its coupe and convertible lineup, replacing the old two-door C-Class and E-Class models with one vehicle that will of course be available in both open- and closed-roof forms. And just to prove the point spy photographers have snapped the AMG versions of both variants on test in Sweden. We know from the performance brake kits, big brakes and quad exhaust setup that these cars are AMG-tuned models, and the fact that those pipes are square, rather than round suggests they’re flagship CLE63 models and not milder AMG-lite CLE43 (or CLE53, depending how AMG chooses to name them) examples.

That should lead us to presume that they’re all running the same 671 hp PHEV four-cylinder powertrain recently revealed in the C63 S E Performance sedan and wagon whose basic platform the new CLE shares. But we were intrigued to see that only one of the three cars (the coupe with the gold brake calipers) is wearing yellow warning stickers to tell emergency service personnel that it’s fitted with a hybrid powertrain.

 

That same car has a charging flap visible below the passenger side tail lamp, but then so does the other coupe, the one without the warning markings. And to further confuse us, the convertible doesn’t appear to have hybrid warning stickers or a charging port. It’s possible that some of these prototypes are older than others and built to different specs, but it’s also conceivable that at least one is a lower-spec version of the CLE63, perhaps without hybrid assistance, or without plug-in functionality. Mercedes-AMG has so far only revealed the C63 sedan in top-dog S E Performance trim, but in the past the C63 was available in both standard and S forms in some markets.

The current C43 sedan runs a 402 hp non-hybrid 2.0-liter turbocharged inline four, whereas the C63’s version of that same engine develops 469 hp before you factor in the hybrid assistance. In theory, AMG could just drop in that C63 motor without the hybrid pack to create a non-S CLE63. It would certainly lose out in the performance stakes, though it could end up weighing hundreds of pounds less.

But we suspect that non-hybrid solution wouldn’t provide the car with enough muscle to sufficiently differentiate it from the C43/53 or justify the 63 badge. What do you think would be the best way to create a non-S 63 drivetrain for the C63 and CLE63?