Butler Built D-Port Aluminum Cylinder Heads w/ Edelbrock Castings, Made in the USA Set/2

Butler-Built Heads on Edelbrock Castings

Need something better than a standard out-of-the-box head? These start as genuine Edelbrock D-Port bare castings and get all of their machine work in the Butler head shop — then they're fitted with Ferrea valves, new guides, and Comp Cams springs, retainers, and locks, with the spring package matched to your camshaft (flat-tappet or hydraulic-roller). Custom built per order for your combination.

The castings have extra-thick port walls and a compact, high-velocity port, which makes them an excellent as-cast street/performance head and an ideal foundation if you ever want them CNC or hand ported later (up to ~325 CFM on D-Port).

Choose Your Build

• Head CC (chamber): 65cc, 72cc, or 87cc — or we can mill a casting to hit your target compression. 72cc builds compression for performance; 87cc keeps a big-inch engine pump-gas friendly.
• Compression Ratio: tell us your target and we'll match the build.
• Cam Specs: supply your known specs so we confirm the correct spring setup.
• Application: tell us the combo so we verify the right components.
• Retainer: standard chromoly, titanium, or PAC-brand titanium with PAC locks.
• Valves: Ferrea 5000 (street performance) or 6000 (competition grade).
• Exhaust Valve Size: standard 1.66" or upgrade to 1.77".
• Rocker Slotting: slot the pushrod holes for the angle needed to run 1.65-ratio rockers.
• Stealth: remove the logos from the ends and above the exhaust ports, with optional paint.
• Intake Gaskets: add a matched set.

Fitment

For 1962–79 Pontiac 389, 400, 421, 428 and 455 V8s (350 with 1.66" exhaust valves and a clearanced block). D-Port keeps the factory-style exhaust port, so these bolt to stock-style manifolds and standard D-port headers. Stock valve-cover and accessory-bolt locations retained.

Intake Flow (D-Port, as-cast core)

Intake, tested on Edelbrock's SuperFlow SF-1020 bench @ 28" H2O:

Full flow sheet (intake & exhaust) available on request.

Compression Reference (with -8cc flat-top piston)

Not sure which chamber you need? Use our compression calculator to dial in your ratio by bore, stroke, gasket, and piston — or call and we'll spec it for you.

Why Edelbrock Castings?

Butler could run our own private-label castings — but cylinder-head metallurgy is unforgiving and foundry quality varies. So we build on the casting the industry trusts: Edelbrock. Every core is sand-cast, heat-treated, and finished in the USA, giving our machine shop a consistent, high-flowing starting point to blueprint to the Butler Standard.

• Casting, core production, pattern making, heat treating, engineering, and machining all done in-house in the USA
• More out-of-the-box flow than most aftermarket aluminum heads — before any porting (capable of ~325 CFM D-Port, ~340 CFM Round Port when CNC ported)
• Heli-Coil inserts in the rocker-stud and exhaust-bolt holes to protect the threads through torque and header R&R

The Butler Process

We don't pull a head out of a box and call it done. Every custom Butler head is built in our own shop: a precision valve job on Serdi seat-and-guide equipment (the same class of machine used in Formula One and top-tier racing), a valvetrain matched to your combination, and flow-bench verification. It bolts on ready to make the power you paid for.

Image may show a bare casting for reference. This item includes two (2) complete, assembled cylinder heads, custom built per order.