For all of its power, the BMW M8 Gran Coupe actually doesn’t sound great. It’s actually a problem with all V8-powered BMW M cars, even the sensational M5 CS. They just don’t sound very good for some reason. However, the folks at Milltek seem to have come up with a good solution.
From the factory, the twin-turbocharged 4.4-liter V8 (S63) makes 617 horsepower and 553 lb-ft of torque. So it’s a monster engine. However, as you can hear in Milltek’s video, it sounds pretty tame. Sure, there’s a bit of a growl at the top end of the rev range but it’s mostly quiet and uninspiring. Which is a shame because the engine itself is so effective. The M8 Gran Coupe is so fast it borders on teleportation, so you want it to sound the part.
The Milltek Sports cat-back, OPF delete exhaust changes that and makes it sound far more appropriate, given its power and prestige. The video shows the differences between the different setups and how much of a difference the full Milltek system makes. With the full-beans system, even in its comfort setting (the exhaust is valved and changes based on the car’s drive modes) it sounds infinitely more aggressive than the stock car.
Switch it to sport mode and things get even angrier. Although, in sport mode, there may be a bit too much exhaust flatulence than I’d personally like. Many customers like that, though, so I get why Milltek engineers that in. Even with the farts and pops on the exhaust, it still sounds great, far better than stock. It’s far more exciting, without being too loud or obnoxious. It’s deep and burbly low in the rev range but, as the revs climb, it gets raspier. The Milltek system makes the M8 Gran Coupe sound as exotic as it looks and is likely well worth whatever it costs.