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SKU: 66-3040 | UPC: 024844079985
K&N 66-3040 X-Stream Top Assembly 14in OD 5.125in Neck Flange 3.063in H - Universal Fit
The K&N 66-3040 X-Stream Top Assembly serves as a performance air filter lid for universal custom air cleaners featuring 14 inch outside diameter filters. It fits applications with 5.125 inch inside diameter neck flanges and stands 3.063 inches tall. This design redirects incoming air to pull through side pleats increasing filter area and airflow efficiency for stronger engine performance.
Key Features
- Added Filter Area: Draws air through side pleats of compatible K&N filter media to expand effective surface area and extend service life
- Airflow Redirection: X-Stream technology channels air inside the filter for higher volume intake and reduced restriction
- Cleanable and Reusable: Wash with K&N cleaning kit and re-oil to restore performance without replacement
- Precise Dimensions: 14 inch OD 5.125 inch neck flange ID and 3.063 inch height ensure drop-in compatibility with standard universal bases
- Engine Protection: Maintains high filtration efficiency even under dirty conditions for reliable power delivery
Product Notes
- Pair with compatible K&N filter element like 14 inch OD high-flow media and matching base plate
- Clean every 50,000 miles or sooner in dusty environments using K&N oil and cleaner
- Arrives ready to install in sealed protective packaging
Installation Notes
- Professional installation recommended.
- Verify base neck ID measures exactly 5.125 inches for secure fit
- Secure with 5.25 inch hose clamp not included for vibration-free mounting
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| Universal | Custom | Air Cleaners | 14" OD Filter Tops |
Why Choose K&N?
- Decades of filtration expertise in motorsports and street applications
- High-flow designs tested on dyno for real-world power gains
- Precision-machined components built to last under extreme conditions
Frequently Asked Questions
-
Q: What filter sizes does the 66-3040 fit?
A: Fits 14 inch outside diameter K&N air filter elements with 5.125 inch inside diameter neck flanges on universal bases -
Q: Can this top be cleaned and reused?
A: Yes fully washable and reusable tap water rinse K&N cleaner and reapply K&N air filter oil -
Q: What warranty covers this part?
A: Backed by K&N limited lifetime warranty when used with genuine K&N filter media and service kits
Shipping & Handling
- Method: UPS Ground or FedEx Ground
- Availability: In stock - ships same or next business day
- Packaging: Manufacturer box 14.25in x 14.25in x 3.75in
- Weight: 0.6 lb
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