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This Spectre breather filter, also known as a crankcase vent filter, has a flange with an inside diameter of 10mm. By using the included adjustable worm gear clamp, this air filter will fit tubes with outside diameters from 3/8 inch to 1/2 inch (8-12mm). Spectre breathers use pre-dyed synthetic media for lasting color, feature a triple chrome-plated steel top and base, and come factory pre-oiled and ready to use. Note: Legal in California only for racing vehicles which may never be used, registered, or licensed for use upon a highway.
Key Features
- This Spectre breather filter, also known as a crankcase vent filter, has a flange with an inside diameter of 10mm.
- By using the included adjustable worm gear clamp, this air filter will fit tubes with outside diameters from 3/8 inch to 1/2 inch (8-12mm).
- Spectre breathers use pre-dyed synthetic media for lasting color, feature a triple chrome-plated steel top and base, and come factory pre-oiled and ready to use.
Fitment
| Application Type | Universal or dimensional component |
|---|---|
| Required Verification | Exact dimensions, material, connection, mounting interface, and companion components |
Specifications
| Brand | Spectre |
|---|---|
| Manufacturer Part Number | 3991 |
| Product Type | Air Filters |
| Fitment Type | Universal or dimensional |
| Condition | New |
What's Included
One new Spectre air filters identified by manufacturer part number 3991. Hardware, clamps, hoses, filters, adapters, and service supplies are included only when stated for this exact product.
About Spectre
Spectre Performance develops air filters, intake systems, intake components, engine accessories, and related vehicle products for direct-fit and dimensional applications.
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Frequently Asked Questions
How do I confirm Spectre 3991 fits my setup?
Match the exact dimensions, material, connection size, mounting interface, and required companion components. Similar appearance alone does not confirm compatibility.
Is Spectre 3991 washable and reusable?
Serviceability depends on the exact filter media. Follow the current Spectre cleaning and oiling directions for this part number and never oil media specified as dry.
What should be checked after installing Spectre 3991?
Verify mounting, clamps, fasteners, seals, hoses, sensors, wiring, and surrounding clearance as applicable. Inspect for leaks or contact before normal operation.
Installation Instructions
Follow the current Spectre instructions for manufacturer part number 3991. Confirm fitment, clean mating surfaces, secure every connection, preserve sensor orientation, check surrounding clearance, and verify emissions requirements before operation.
Spectre
Shop Spectre air intake systems, replacement air filters, intake tubing, couplers, clamps, engine accessories, and service products by exact manufacturer part number and verified application.Choosing the Correct Spectre Product Match the complete Spectre manufacturer part number Confirm the listed year, make, model, engine, and emissions notes for direct-fit products Verify diameter, material, bend, connection, sensor, and mounting details for universal components Review included filters, clamps, adapters, hardware, and current installation instructions Vehicle FitmentVehicle-specific products use collapsed year ranges and canonical year, make, model, and only legitimate required submodel data for Convermax filtering. Engine displacement, engine configuration, fuel type, drivetrain, and chassis codes remain application details rather than vehicle models.Related Spectre Products All Spectre products Cold air intakes Air filters Air intake components Frequently Asked QuestionsHow do I...
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