M Sport Brakes - G20, G22

Revised 10/18/2022
This page is evolving as we continue to find exceptions and changes made in the middle of production.

The brake options on the G20 3-series and G22 4-series are much less confusing than their predecessors but there is still some confusion that needs clearing up. Luckily, it seems internet forums have already caught on to the differences and we included links to them below.

There are five factory brake options offered on G20 3-series and G22 4-series: 30i standard, 30i M Sport, M40i standard, Motorsport Engineering, and M Performance.

330i/430i Standard Brakes

Base model brakes with single-piston sliding calipers front and rear. The pads look familiar since this a traditional caliper type.
Front Rotor: 330x24mm, 1-piece, blank face rotors
Rear Rotor: 330x20mm, 1-piece, blank face rotors
Front Caliper: 1-piston, sliding, grey/unfinished
Rear Caliper: 1-piston, sliding, grey/unfinished

330i/430i M Sport Brakes

If the M Sport package was selected at the time of ordering the brakes were upgraded to M340i/M440i specs. See below.

M340i/M440i Standard Brakes (M Sport)

As a full M Sport model the M340i and M440i received appropriate M Sport brake upgrades. These are Brembo 4-piston fixed calipers in the front and single-piston sliding calipers in the rear. These were offered in either blue or red color. The M Sport pads are unique to match the size of the M Sport 348mm rotor. The front pads measure 125.8 x 94.7mm.
Front Rotor: 348x36mm, 2-piece, blank face rotors
Rear Rotor: 345x24mm, 2-piece, blank face rotors
Front Caliper: 4-piston, fixed, blue or red
Rear Caliper: 1-piston, sliding, blue or red

M340i/M440i Motorsport Engineering/Track Package Option

In the BMW parts diagrams there is a listing for the "Motorsport Engineering" optional brakes. It's option code 033 (aka S033T or 033T or ZTK). We think this is a rare option and may not be offered in all markets. It was not offered for 330i/430i. The rotor size was increased to 374mm and the fixed caliper was changed for the extra 26mm of rotor diameter. Although the calipers look almost identical - and share some of the same components - they are slightly different. The pads are also different with the larger brakes getting a larger pad (127.7 x 117.4mm). The rear caliper remained a sliding single-piston design. These calipers were also offered as blue or red color. These brakes should clear most 18" wheels, however, BMW required 19" wheels when the package was ordered.
Front Rotor: 374x36mm, 2-piece, blank face rotors
Rear Rotor: 345x24mm, 2-piece, blank face rotors
Front Caliper: 4-piston, fixed, blue or red
Rear Caliper: 1-piston, sliding, blue or red

M Performance Accessory Brakes (all models)

Available from the Accessories catalog, the M Performance brakes are a dealer-installed option. These match the specs of the Motorsport Engineering brakes but were only offered in the red color. The pads are the same as the ZTK track brakes. These brakes should clear most 18" wheels.
Front Rotor: 374x36mm, 2-piece, dimpled & slotted rotors
Rear Rotor: 345x24mm, 2-piece, dimpled & slotted rotors
Front Caliper: 4-piston, fixed, red
Rear Caliper: 1-piston, sliding, red

How To Tell
You can't tell which brakes you have by the color. Just because you have red calipers does not mean you have an upgraded brake kit.
You can't tell which brakes you have by the caliper - they are extremely similar in appearance.
The best way we have found so far is to measure from the exact middle of your wheel center cap to the outer edge of your brake rotor. Over 7 inches is the 374mm rotor; under 7 inches is the 348mm rotor.