-12%
Click to zoom in
SKU: RX-4140 | UPC: 024844043238
K&N Universal X-Stream Clamp-On Round Air Filter 3.531in Flg ID/4in OD/5.969in H
The K&N RX-4140 universal X-Stream clamp-on air filter fits custom intake systems on racing vehicles and performance builds requiring a 3.531 inch flange inside diameter. Its innovative top design increases filter media for greater airflow and dust protection in demanding conditions. This washable reusable filter ensures consistent engine power with easy clamp-on installation.
Key Features
- X-Stream Top Design: Built-in pleated filter adds media area inside the top section for higher airflow rates and extended service intervals
- Clamp-On Mounting: Pliable rubber flanges stretch up to 1/16 inch for secure fit on 3.531-3.547 inch openings while absorbing vibration
- Low Restriction Flow: Pleated cotton gauze media delivers maximum air volume to support high-horsepower engines
- Round Tapered Shape: 3.531 inch flange ID 4 inch flange OD and 5.969 inch height suits compact custom setups
- Washable Reusable Media: Clean with K&N kit and re-oil for thousands of miles of service without replacement
Product Notes
- Ideal for racing setups needing strong filtration in dusty or dirty environments
- Molded rubber flanges provide vibration resistance and centered alignment
- 0.813 inch flange length ensures stable mounting on throttle bodies or carbs
Installation Notes
- Professional installation recommended.
- Clamp directly to 3.531 inch ID intake tube or carburetor with hose clamp
- Oil filter media after cleaning per K&N instructions for peak performance
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| Universal | Various | Custom Intakes | Racing Performance Builds |
Why Choose K&N?
- Proven leader in performance filtration for motorsports worldwide
- Cotton gauze construction traps dirt while passing more air than paper filters
- Engineered dimensions and materials for reliable custom applications
Frequently Asked Questions
-
Q: What flange size does the RX-4140 fit?
A: Centered flange with 3.531 inch inside diameter 4 inch outside diameter and 0.813 inch length fits most custom throttle bodies in that range -
Q: What media material is used?
A: Four layers of oiled cotton gauze pleats provide high airflow and particle capture down to 5 microns -
Q: What warranty applies?
A: K&N No-Hassle Lifetime Warranty covers defects when cleaned and maintained properly
Shipping &. Handling
- Method: UPS Ground
- Availability: In stock - ships same or next business day
- Packaging: Original K&N box 7in x 7in x 7in
- Weight: 1.1 pounds
Read More
Air Filters
Welcome to our collection of high-quality Air Filters, designed to enhance the air quality in your home or office. Our carefully curated selection features a variety of air filters suitable for different needs, ensuring you breathe easy in any environment. Whether you are looking for HEPA filters, activated carbon filters, or specialty filters, you will find the perfect solution to keep your space fresh and clean. Why Choose Our Air Filters? Our Air Filters provide exceptional performance and durability. Here are some key benefits: Enhanced Air Quality: Removes dust, allergens, and pollutants, promoting a healthier atmosphere. Energy Efficiency: Designed to optimize airflow, reducing energy costs while maintaining effectiveness. Variety of Options: Available in various sizes and types to fit most HVAC systems and air purifiers. Shop with Confidence All our Air Filters are sourced from trusted manufacturers, ensuring you receive reliable products that meet strict quality ...
View Air Filters Products
Air Filters - Universal Fit
Welcome to our exclusive collection of Air Filters - Universal Fit, designed to meet the diverse needs of your vehicle. These filters are essential for maintaining optimal engine performance and air quality, ensuring a smoother ride and enhancing the longevity of your automobile. Our universal fit air filters are crafted with quality materials, providing superior filtration efficiency and ease of installation. Key Features of Our Air Filters - Universal Fit Versatile Compatibility: These air filters are designed to fit a wide range of vehicles, making them a smart choice for any car owner. High Filtration Efficiency: Our filters effectively trap dirt, dust, and debris, ensuring only clean air enters your engine. Easy Installation: With a universal fit design, installation is straightforward and can be done without professional help. Durable Construction: Made from high-quality materials, our air filters are built to last, providing reliable performance. Why Choose the ri...
View Air Filters - Universal Fit Products
K&N Engineering
Cold Air Intakes, Air Filters, Oil Filters & Performance Filtration Browse premium K&N Engineering performance parts and filters at Black Ops Auto Works, including cold air intakes, replacement air filters, universal air filters, oil filters, cabin air filters, fuel filters, filter cleaning kits, air intake accessories, and performance filtration upgrades for cars, trucks, SUVs, diesel applications, off-road vehicles, and performance builds. K&N is one of the most recognized names in automotive filtration and airflow technology, trusted by enthusiasts who want better airflow, reusable filter performance, and dependable engine protection. Why Choose K&N Engineering K&N products are engineered to improve airflow and support performance-focused driving across street, towing, off-road, and high-performance applications. Popular reasons drivers choose K&N include: Improved airflow and throttle response Reusable, washable air filters Long-term filtration value Veh...
View K&N Engineering Products