K&N High-Flow Air Filter BMW M135i, M235i & 435i (N55 3.0L)

K&N High-Flow Panel Air Filter for BMW M135i, M235i & 435i (N55 3.0L)

Part No: 33-2997  Quantity Required: 1 (Filters are sold individually)

Your M135i, M235i or 435i is already a seriously special car. The N55 3.0-litre turbo straight-six is smooth, punchy and hugely tuneable – it’s the heart of the whole experience. But from the factory, it’s breathing through a restrictive, throwaway paper filter that prioritises cost and emissions over performance.

It’s time to let the engine breathe properly. The K&N High-Flow Panel Air Filter is the ideal “first mod” for any N55-powered BMW. It drops straight into the original airbox and is engineered to be the last air filter you’ll ever need to buy for the car.

Using K&N’s multi-layered, oiled cotton gauze, this filter allows significantly more airflow than the standard paper element while still providing excellent filtration. The result is sharper throttle response, stronger pull through the rev range, and a more pronounced induction sound that really lets you hear that straight-six at work.

And unlike the stock filter, this K&N is fully washable and reusable. When it’s dirty, you simply clean, re-oil and refit – no more buying a new filter at every service.

Key Features & Benefits:

• Unlocks Performance: Increased airflow to your N55 engine, supporting improved horsepower and torque compared to the standard paper filter.

• Sharper Throttle Response: Noticeably more eager pick-up and reduced “choking” at higher revs as the turbo can draw air more freely.

• Reusable Design: Fully washable and reusable – simply clean and re-oil instead of replacing, saving money over the life of the car.

• Direct Drop-In Replacement: Fits directly into the OEM airbox with no cutting, drilling or extra parts required.

• Excellent Engine Protection: Multi-layer oiled cotton gauze traps fine particles while still allowing far greater airflow than paper.

• Great Supporting Mod for Tuning: Perfect partner for an ECU remap or other performance upgrades, removing a key intake restriction.

MSL Recommends:
Your N55 engine uses a single panel filter in the factory airbox, so you only need one (1) of these filters per car. Ideal as a simple, cost-effective upgrade on a stock car and an excellent supporting mod for future tuning plans.

Full Vehicle Fitment List

This filter (33-2997) is designed for the following BMW models with the N55 3.0L turbocharged straight-six and standard airbox:

• BMW M135i / M135i xDrive – F20 / F21

• BMW M235i / M235i xDrive – F22 Coupé, F23 Convertible

• BMW 435i / 435i xDrive – F32 Coupé, F33 Convertible, F36 Gran Coupé