The M3 and M4 cats are out of the bag. Both of them get a twin-turbo inline-six first introduced by the X3 and X4 M crossovers and both can deliver up to 503 horsepower in Competition trim. Standard stuff aside, BMW is letting customers spice up its polarizing coupe and sedan with a long list of M Performance bits and bobs.

Show me the goodies!

That said, know that you can spice up the sound of your M3/M4 with a lightweight titanium exhaust setup. BMW says it’s five kilos (11 pounds) lighter than the stock setup. It also doubles down on design thanks to the quad-offset, ceramic-coated final pipes.

Or, if vanity is not your thing, you can specify the M Performance sports suspension which brings the car 10 mm (0.4 inches) closer to the ground, or the M Performance brake pads that beg for abuse on the track. After all, you can still spec both the M3 and the M4 with an optional six-speed manual transmission.

Moving on to visual cues, there’s a bunch of carbon fiber parts that can add extra gusto to the exterior:

-* front attachment

-* front splitter

-* aero flicks

-* air breathers

-* side skirts

-* rear winglets

-* rear spoiler

-* rear diffuser

Wheels were also a focal point of BMW’s M Performance range for the new M3 and M4. As a result, you can pick wheels that range from 19 to 21 inches:

-* M Performance Y-spoke forged 963M in Frozen Gunmetal Grey (19 inches in the front, 20 in the rear)

-* M Performance cross-spoke forged 1000M in Gold Bronze matte or Jet Black matte (20 inch in the front, 21 inch in the rear)

That’s all? What about the interior?

There’s plenty of stuff to specify for in the cockpit of your new M3/M4:

-* M Performance door sills

-* contrasting stitching

-* matt-coated carbon fiber trim

-* Alcantara

-* LED door projectors

-* M Performance wallet key

On demand, BMW can offer M Performance carbon shift paddles.

Last but not least, there’s the M Performance indoor car cover for those winter months during which your bucktooth-grille track monster is hibernating.