Spectre Coupler 4in. (PVC) - Black

The Spectre Coupler 4in. (PVC) in Black (part number 9771) is a straight-style PVC silicone coupler designed to join two 4-inch OD intake tubes, ducting hoses, or air box connections in naturally aspirated applications. The 9771 provides a secure, air-tight connection with included stainless steel worm-gear hose clamps, making it a fast and reliable solution for custom cold-air intake builds, air box extensions, and intake ducting repairs. Note: this coupler is not rated for pressurized applications such as turbocharger or supercharger outlets.

Features and Benefits

• 4-inch inside diameter fits standard 4in OD intake tubes and ducting components
• PVC construction provides flexibility for easy installation and vibration absorption
• Black finish blends cleanly with most engine bay setups
• Includes stainless steel worm-gear hose clamps for secure, rattle-free retention
• Straight coupler design for direct tube-to-tube connections at the same diameter
• Suitable for naturally aspirated cold-air intake, ram air, and inlet ducting applications
• Lightweight and easy to trim if needed for tight fitment scenarios
• Spectre quality construction for consistent material thickness and durability

Specifications

What's Included

• 1 x Spectre 9771 PVC straight coupler (4in ID, black)
• Stainless steel worm-gear hose clamps

Frequently Asked Questions

What tube size does the Spectre 9771 fit?
The 9771 is sized for 4-inch inside diameter, which mates with standard 4in OD tubing used in most large-diameter cold-air intake kits and air duct assemblies.

Can the Spectre 9771 be used on a turbocharged or supercharged vehicle?
No. This coupler is PVC construction and is not rated for pressurized systems. It is intended for naturally aspirated intake and ducting use only. For boosted applications, use a silicone coupler rated for boost pressure.

Does the 9771 include hose clamps?
Yes, stainless steel worm-gear hose clamps are included with the Spectre 9771 for secure, leak-free installation.

What is the difference between the 9771 and the 97711?
Both are 4-inch black PVC straight couplers, but they may differ in length or wall construction. The 9771 is the standard straight coupler version. Check the dimensions before ordering if you have strict length requirements.

Is the Spectre 9771 compatible with aluminum intake tubes?
Yes. PVC couplers work with aluminum, plastic, ABS, and steel tubes of the correct diameter. The clamps grip the outer surface of whatever tube you insert into the coupler.

Can this coupler be painted or wrapped?
PVC does not hold paint well without primer. For cosmetic changes, use heat-wrap tape or a rubber-compatible spray primer before applying color. Alternatively, the black color blends unobtrusively in most engine bays as-is.

Will this work as a replacement coupler in a factory intake system?
The 9771 can work as a service replacement if the factory connection uses a 4-inch straight coupler with worm-gear clamp retention. Confirm the OD of your factory tubing and the existing coupler dimensions before ordering.

How should the 9771 be installed to prevent leaks?
Insert both tube ends fully into the coupler, center the coupler on the joint, and tighten each worm-gear clamp evenly to 30-35 in-lb. Over-tightening can deform the PVC, so use a torque screwdriver or hand-tighten snugly with a nut driver.

Installation Instructions

1. Ensure all intake tube ends are clean and free of burrs or sharp edges that could damage the coupler.
2. Slide one hose clamp over each tube end before insertion.
3. Insert one tube end fully into one side of the Spectre 9771 coupler, centering the tube in the coupler bore.
4. Insert the second tube end into the opposite side of the coupler.
5. Position each hose clamp over the coupler-to-tube overlap zone, approximately 0.5in from the tube end.
6. Tighten clamps evenly to secure the coupler without over-compressing the PVC.
7. Inspect the assembly for any gaps or misalignment before returning to service.

Proposition 65 Warning: This product can expose you to chemicals including Diisononyl Phthalate (DINP), which is known to the State of California to cause cancer. For more information, go to www.P65Warnings.ca.gov.