K&N 33-2530 High-Flow Washable Panel Air Filter - Vintage BMW & Porsche Fit

Vehicle / Engine Fitment

• BMW 3-Series (E21) 320/320i/323i - model years 1977-1982
• BMW 5-Series (E12) 520i - model years 1972-1977 (some listings extend to 1977)
• BMW 2500 / 3.0 / 3.3 (E3) sedans - model years 1971-1977
• Porsche 911 (various generations) - model years 1977-1993
• Porsche 930 (911 Turbo & related) - 1976-1989 (varies by region/model) including many 3.0L-3.3L engines

Features

• High-flow oiled cotton-gauze media for improved airflow vs standard paper filters
• Washable & reusable design - clean, re-oil and reuse instead of frequent replacements
• Drop-in replacement - installs directly into stock air box when correct for vehicle
• Multi-layer filtration - balances airflow and particulate filtration, protecting engine while increasing breathing
• Pre-oiled and ready for installation - no prep required out of the box
• Enhanced engine breathing - can improve throttle response and performance under load
• Durable construction - designed to last for many years with proper maintenance
• Lifetime-limited warranty (when maintained per instructions)

Specifications

• Filter type: Panel air filter
• Filter media: Oiled cotton-gauze
• Dimensions (approx): 14" x 8" x 0.875" (length x width x height)
• Washable/re-usable: Yes
• Typical maintenance: Clean and re-oil periodically per driving conditions
• Warranty: Lifetime limited (manufacturer warranty when maintained properly)

Included Components

• 1x reusable panel air filter (33-2530)

Product Description

The K&N 33-2530 is a premium, washable and reusable panel air filter designed as a direct replacement for stock filters on a range of classic BMW and Porsche vehicles. With oiled cotton-gauze media and multi-layer construction, it provides superior airflow compared to conventional paper filters - which can help improve throttle response, engine breathing, and performance under load. Because it's a washable design, the filter can be cleaned, re-oiled, and reused many times, reducing long-term maintenance costs and waste.

This filter is particularly suited for owners of older cars - such as late-'70s to early-'90s BMW 3-Series, 5-Series, 2500/3.0/E3 sedans, or various generations of the classic Porsche 911 and 930 - who want a balance of improved airflow and proper filtration without modifying their intake systems. Installation is generally a simple drop-in when the airbox and filter housing match the standard dimensions. For long-term durability and peak performance, follow K&N's cleaning and re-oiling schedule, and ensure the filter seals properly in the air box before closing it up.

WARNING: Fitment Note: Because 33-2530 is designed for older BMW and Porsche cars, always verify that your vehicle's model year, engine code, and air-box dimensions match the original specification before installation. Use this filter only in vehicles where 33-2530 is confirmed or cross-referenced.