Butler Built Round Aluminum Cylinder Heads w/ Edelbrock Castings, Made in the USA (Pair)

Butler-Built Heads on Edelbrock Castings

Need something better than a standard out-of-the-box head? These start as genuine Edelbrock Round 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, matched to your camshaft. Built to the same specifications as our popular Performer RPM 61519 Round Port head for 1962–79 455 Pontiac engines, with the option of a CNC-machined chamber for a precise, repeatable chamber and cleaner combustion.

Both chamber sizes are patterned after the 1969–70 Ram Air IV Round Port flange: the 87cc is ideal for ~10:1 engines and strong street performance on low-octane fuel, while the 72cc suits higher-compression builds. As shipped, these come equipped with springs for hydraulic-roller camshaft applications (tell us your cam and we'll confirm the package).

Choose Your Build

• Chamber Finish: as-cast, hand-polished, or CNC-machined.
• Head CC (chamber): 72cc or 87cc — or we can mill a casting to hit your target compression.
• 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 1.65-ratio rockers.
• Stealth: logo removal with optional paint.
• Intake Gaskets: add a matched set.

Fitment

For 1965–79 Pontiac 389–455 V8s. Round Port heads use the Ram Air IV exhaust flange, so you'll need round-port headers (or Ram Air manifolds) to match. Stock valve-cover and accessory-bolt locations retained.

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.