RoyalAir 1/4" Phenolic Carburetor Spacer 4-Hole — Direct-Fit for Holley/Edelbrock, Heat-Reducing

RoyalAir 1/4 inch phenolic carburetor spacer with four holes provides a thermal barrier between carburetor and intake manifold to improve throttle response and help maintain cooler fuel temperatures.

If you run a Holley 4150/4160, Edelbrock Performer, or similar carburetor, the right spacer can make measurable differences in driveability and consistency. This RoyalAir spacer is machined to match common 4-bolt carb bases and uses phenolic material to reduce heat transfer from the intake manifold. It’s a direct-fit alternative to the Canton Racing 85-154 layout and intended for straightforward installation with standard mounting hardware.

How does this spacer affect throttle response and mixture distribution?

The 1/4" thickness combined with four precisely machined ports helps even out airflow under the carburetor, which can smooth throttle transitions and reduce hesitation. By adding spacing between the carb and manifold, the spacer gives the fuel-air charge a small pocket to better atomize before entering the runner.

• 1/4" thickness creates a short plenum for improved atomization
• Four-hole configuration maintains factory-aligned ports for even flow
• Precision-machined openings reduce turbulence at the carb base

Will this spacer reduce heat-related fuel issues like vapor lock?

Phenolic is chosen for its low thermal conductivity, so installing this spacer places a thermal barrier between the hot intake and the carburetor body. That separation helps keep fuel temperatures lower at the carb mounting surface and can reduce the likelihood of vapor formation in warm operating conditions.

• Phenolic construction minimizes heat transfer into the carb body
• Physical gap decreases direct manifold heat conduction
• Compatible with high-temperature engine environments without warping

Is installation complicated for a home mechanic?

Installation is intentionally simple: the spacer includes four mounting holes aligned to standard carburetor bolt patterns and requires only common tools for fitting. No specialty gaskets beyond the appropriate intake and carburetor seals are usually needed, and the spacer matches Holley 4150/4160 and many Edelbrock bolt patterns for direct replacement.

• Uses standard four-corner mounting hardware
• Direct-fit for Holley 4150/4160 and Edelbrock Performer series
• Compatible with existing carb and intake gaskets for most installations

What materials and dimensions should I expect?

The spacer is molded from robust phenolic resin to combine light weight with thermal resistance. It measures 1/4 inch thick and features four accurately located openings and corner bolt holes to match OEM-style carburetor bases.

• Material: high-strength phenolic
• Thickness: 1/4 inch (6.35 mm)
• Pattern: four-hole carburetor mounting with precision-machined ports

Who is this for: This RoyalAir spacer is aimed at street and performance enthusiasts, restoration builders, and DIY mechanics who use Holley 4150/4160 or Edelbrock-style carburetors and want a reliable, low-cost thermal spacer. It’s suitable for engines where improved throttle response, reduced carb heat soak, and a direct replacement to Canton Racing 85-154 mounting geometry are desired. If you need a straightforward, durable phenolic spacer that installs with standard hardware, this part is a practical, engine-bay-friendly upgrade.