K&N Engineering Replacement Air Filter

BMW 525i L6-2.5L 24V (M50) 1998–2003

Part #: 33-2078

Overview

The K&N Engineering Replacement Air Filter for the BMW 525i with the 2.5L inline-six engine is designed to deliver improved airflow and filtration efficiency for your vehicle. Crafted specifically for BMW enthusiasts and daily drivers alike, this high-performance filter helps support increased horsepower and torque while maintaining excellent engine protection. Whether you're looking to enhance your driving experience or ensure your engine breathes easier, this filter is an ideal upgrade.

Engineered to fit seamlessly into your BMW 525i, this filter replaces the factory unit with a durable, reusable design that can be cleaned and reused multiple times. Its high-flow capabilities help optimize airflow, resulting in better throttle response and potentially improved fuel efficiency. Perfect for those seeking a reliable, long-lasting upgrade that combines performance with convenience.

Key Features

The K&N Replacement Air Filter boasts several key features that make it a top choice for performance-minded drivers:

• Constructed with multiple layers of high-quality, oiled cotton media that provide excellent filtration while maximizing airflow.
• Designed with a durable, epoxy-coated aluminum wire mesh to maintain shape and prevent collapse under high airflow conditions.
• Reusability allows for cleaning and re-oiling, offering long-term cost savings and environmental benefits.
• Engineered to meet or exceed OEM filtration standards, ensuring your engine remains protected from dirt, debris, and contaminants.
• Precision-made to fit the BMW 525i (E39 chassis, M50 engine) perfectly, ensuring a secure seal and optimal performance.
• Improves airflow compared to the factory paper filter, supporting better engine breathing and responsiveness.
• Backed by the trusted K&N reputation for quality and performance in the automotive aftermarket industry.

Filter Options

This product features a high-flow, oiled cotton media that is designed for maximum performance and filtration efficiency. The filter is washable and reusable, allowing you to maintain peak performance with proper cleaning and oiling. It is suitable for spirited driving, daily commuting, and performance upgrades, providing a balance of filtration and airflow that benefits your engine's health and power output.

Construction & Design

The K&N air filter is built with a rugged, epoxy-coated aluminum wire mesh that supports the high-quality cotton media, ensuring durability and shape retention over many cleaning cycles. The multi-layer cotton media is specially oiled to trap dirt and debris effectively while allowing unrestricted airflow. Its precision design ensures a perfect fit within the factory air box of your BMW 525i, eliminating any air leaks and maintaining optimal sealing. The filter's construction emphasizes longevity, ease of maintenance, and consistent performance, making it a reliable upgrade for your vehicle.

Installation & Fitment

Installing the K&N Replacement Air Filter is a straightforward, bolt-on process that requires no special tools or modifications. Simply remove the factory filter from your BMW 525i's air box and replace it with this high-performance unit. No cutting, drilling, or tuning is necessary. The filter is designed to fit precisely within the OEM air box, providing a secure seal and optimal airflow. This makes it an excellent upgrade for DIY enthusiasts and professional technicians alike.

What's Included

• High-flow, reusable K&N cotton air filter designed specifically for BMW 525i (E39 chassis, M50 engine)
• Installation instructions for proper maintenance and cleaning

Ideal For

• BMW 525i owners seeking improved engine breathing and performance
• Enthusiasts looking for a durable, reusable air filter that reduces ongoing replacement costs
• Drivers wanting to enhance throttle response and engine sound without extensive modifications
• Anyone committed to maintaining optimal filtration while supporting increased airflow