Build Your Own Heads Kits

The Core Offering: Pre-Machined Castings

The cornerstone of the Build Your Own Heads Kits is the cylinder head casting itself, which comes with all of Butler’s critical machine work already completed.²

• Premium Castings: The kits start with brand new aluminum castings, typically Edelbrock Performer RPM D-Port or Round Port heads, but are also available using Speedmaster castings.

• Ready for Assembly: The castings are delivered with all the required machine work performed by Butler Performance, including:

  • Valve Guides and Seats: Guides are installed, and the valve seats are machined with a precision multi-angle valve job, ensuring perfect valve-to-seat sealing.

  • Spring Pockets: The spring pockets are machined to the correct depth to achieve the required installed height for the valvetrain components.

  • Rocker Studs and Guideplates: Often installed and correctly aligned, allowing for immediate assembly.

• Porting Options: Builders can select the level of airflow required:

  • Unported Kits: For those seeking great street performance without the cost of full porting.

  • CNC Ported Kits: For maximum performance, these heads come with Butler's proprietary CNC porting already completed, providing high, consistent airflow (up to the 325cfm range or more, depending on the kit).

The Kit Contents: High-Quality Valvetrain Components

The Build Your Own Heads Kits include all the high-quality valvetrain components that Butler uses in their own crate engines, ensuring a perfectly matched system:³

• Valves: High-quality, severe-duty stainless steel intake and exhaust valves (e.g., 2.11 inch intake and 1.66 inch exhaust for D-Port heads).

• Valve Springs: Dual or single valve springs are supplied, specifically matched to handle the pressures and lift of common performance camshafts (hydraulic flat tappet or hydraulic roller).

• Retainers and Locks: Chromoly steel or lightweight Titanium Retainers (for maximum performance builds) and matching locks are included.⁷

   

   

• Seals and Hardware: High-temperature Viton valve stem seals, spring seats/locators, and shims are provided to ensure the builder can set the final installed height and spring pressure precisely to specification.⁸

   

   

Why Choose a Builder Kit?

1. Final Assembly Control: The builder or their local machine shop can verify all component clearances, measure for the perfect pushrod length, and set the valve spring installed height and pressure with their own tools—a critical step in any performance build.

2. Custom Cam Matching: While Butler supplies performance springs, the final assembly allows the builder to perfectly match the spring package to an extremely custom or proprietary camshaft that may not be standard in a fully assembled head kit.

3. Cost and Time Savings: Eliminates the final assembly labor charge from Butler and simplifies inventory for builders who already possess the expertise and tools to assemble cylinder heads.

By offering these meticulously prepared, component-rich "Build Your Own Heads Kits," Butler Performance enables the sophisticated enthusiast to achieve the quality and consistency of a professionally-built cylinder head while retaining total control over the final valvetrain setup.