The K&N E-3740 is a direct replacement round air filter with 14 inch outside diameter 12 inch inside diameter and 2.313 inch height for increased engine airflow. It fits factory air boxes in 1979-1986 Peugeot 604 models and 1985-1994 Ford Scorpio increasing horsepower and acceleration while protecting the engine. Washable and reusable this filter delivers high air volume for better performance in these classic vehicles.
Key Features
- High Airflow Design: Reduces intake restriction to deliver more air to the engine for gains in horsepower and quicker acceleration.
- Product weight 1.3 lb ships in compact box.
- High flow cotton media balances power gains with engine protection.
- Compatible with OEM air box hardware and vehicle electronics.
- Multi-layer oiled cotton gauze provides high airflow and traps dirt while allowing easy cleaning and re-oiling.
Fitment
| Years | Make | Model | Application |
|---|---|---|---|
| 1979-1980 | Peugeot | 604 | SL |
Specifications
| Brand | K&N Engineering |
|---|---|
| Manufacturer Part Number | E-3740 |
| Product Type | Air Filters - Drop In |
| Fitment Type | Vehicle Specific |
| Condition | New |
What's Included
One new K&N air filters - drop in identified by manufacturer part number E-3740. Hardware, adapters, clamps, hoses, filters, and service supplies are included only when stated for this exact product.
About K&N Engineering
K&N develops reusable air filtration, intake, oil filtration, fuel filtration, and related performance products for vehicle-specific and dimensional applications.
Related K&N Engineering Products
- Shop all K&N Engineering products
- K&N Custom Round Air Filter 14in OD 12in ID 4in Height
- K&N Custom Air Filter 14in OD / 12in ID / 6in Height
- K&N Custom Air Filter Round 2.875in ID x 3.875in OD x 2in Height
Frequently Asked Questions
How do I confirm K&N E-3740 fits my vehicle?
Match the year, make, and model in the fitment table, then confirm the engine, factory housing, sensor layout, emissions notes, and any application restrictions stated for this exact part.
Is K&N E-3740 washable and reusable?
Serviceability depends on the exact media used for this part number. Follow the K&N cleaning and oiling directions for this filter and never apply oil to media specified as dry.
What should be checked after installing K&N E-3740?
Verify seals, clamps, fasteners, hoses, sensors, wiring, and surrounding clearance as applicable. Check for leaks or contact, then follow the manufacturer service and reinspection schedule.
Installation Instructions
- Remove stock filter and drop E-3740 into factory air box no cutting or drilling
- Compatible with OEM air box hardware and vehicle electronics
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