CoretorTex 1" Phenolic Carburetor Spacer for Square-Bore 4BBL — 1in Insulating Spacer with Gaskets & Hardware

CoretorTex 1-inch phenolic carburetor spacer designed for square-bore 4-barrel carburetors—includes gaskets and mounting hardware for Chevy, Ford and other V8 applications.

This phenolic spacer raises the carburetor 1 inch above the intake flange, using heat-resistant phenolic material to reduce heat soak into the carburetor while maintaining correct throttle response and mixture distribution. It is machined for a square bore and supplied with two gaskets, bolts, washers and nuts to make installation straightforward on compatible Holley AFB, Edelbrock and other square-bore 4BBL carburetors used on SBC, BBC and big-block Ford engines.

Will this 1" spacer fit my carburetor and engine?

The CoretorTex spacer is made for square-bore four-barrel carburetors and uses M8 x 1.0 threaded fasteners. It’s commonly compatible with Holley AFB and many Edelbrock 4BBL units when the carb and intake have the same bolt pattern and bore type. Always confirm physical measurements and bolt thread size before installing.

• Thickness: 1.0 inch phenolic material
• Bore type: square bore for 4BBL carburetors
• Thread specification: M8 x 1.0
• Typical engines: Chevy SBC/BBC/Big Block, Ford 350 and comparable V8s

How does a phenolic spacer affect carburetor temperature and performance?

Phenolic is an insulating material that limits heat transfer from the intake manifold to the carburetor, reducing heat-soak that can cause fuel vaporization and poor cold-idle or off-idle response. While not a performance tuner by itself, it helps maintain more stable fuel delivery and can support consistent tuning. Results depend on overall engine setup and tuning.

• Insulates carburetor from manifold heat
• Helps reduce vapor lock and hot-idle issues
• Maintains carburetor base temperature for consistent mixture
• Works best combined with proper jetting and ignition timing

What is included in the kit and what do I need for installation?

The CoretorTex kit includes everything required to mount the spacer between carburetor and intake flange for compatible applications: one phenolic spacer, two gaskets, and a set of four bolts, washers and nuts. Installation requires basic hand tools and verification that the bolt pattern and thread pitch match your carburetor and intake.

• 1 x 1" phenolic spacer
• 2 x carburetor gaskets (top and bottom)
• 4 x bolts, 4 x washers, 4 x nuts (M8 x 1.0 fitment)
• Simple tools: wrench/sockets, torque wrench recommended

Are there any fitment warnings or installation tips?

Double-check that the spacer’s square bore and M8 x 1.0 threads match your carburetor and intake. Phenolic is durable but should be installed with even torque on mounting hardware; avoid overtightening. Confirm clearances for linkage, fuel lines and air cleaner height before final installation to prevent interference.

• Verify part dimensions and bolt pattern against your carb
• Torque bolts evenly to avoid cracking the spacer
• Check choke and throttle linkages for proper travel
• Measure air cleaner clearance after spacer installation

Who this is for: This CoretorTex 1" phenolic spacer is aimed at enthusiasts and mechanics fitting square-bore 4-barrel carburetors on SBC, BBC and similar V8 engines who want a simple, cost-effective way to reduce carburetor heat soak and stabilize fuel delivery. It’s suited to restoration projects, street machines and mild performance builds where insulating the carburetor helps drivability without major modifications. If you’re uncertain about fitment, compare bolt patterns, bore type and thread size before ordering to ensure compatibility.