AC Schnitzer’s latest tuning upgrade for the BMW M3 and M4 isn’t that impressive but only if you think that 510 PS (503 hp) and 654 Nm (482 lb-ft) of torque are not enough.
Thanks to their turbocharged, 3.0-litre S55 inline-six, the Bavarian vehicles are a tuner’s dream, mainly because the engine can be easily upgraded to produce impressive amounts of power.
The power bump came mainly from an ECU upgrade, lifting the engine’s output from the factory’s 431 PS (425 hp) to 510 PS (503 hp), and from 550 Nm (405 lb-ft) to 645 Nm (482 lb-ft).
Okay, AC Schnitzer’s re-worked exhaust with silencers, flap control and sound pipe might’ve helped a bit, by improving the gas flow, but at the end of the day it all boils down to the revamped engine control unit.
Both vehicles can be commissioned with either AC Schnitzer’s suspension spring kit (which lowers the car by around 25 – 30 mm at the front and 10 – 15 mm at the rear) or the RS adjustable suspension (slamming the car closer to the ground by 30 – 40 mm at the front and around 30 mm at the rear). Both solutions improve cornering, offer “gentle” understeer at the limit and a good-natured load change.
Exterior-wise, a meticulously crafted aerodynamic package was implemented. Composed of a multistage body styling kit, the final Stage 3 variant features super-lightweight carbon front spoiler elements (which weigh only 400 grams), including a racing splitter, carbon fiber side wings, rear and roof spoilers, and even carbon fiber mirror covers.
A similar theme can be found at the interior, as the German tuner bedizened the vehicles with various enhancements, ranging from the aluminum pedal set and foot rest, to the aluminum gear knob with digital gear display and handbrake handle.