Butler Performance Edelbrock Round Port/Wide Port CNC Machined Pontiac 72cc 370+CFM Cylinder Heads, Solid Roller, (Pair) BPI-72cc-EDL-RdPort-370CNC-WP

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Butler Performance's Wide Port Wonder
Butler Performance in Leoma, Tennessee, is among the most recognizable names within the Pontiac hobby, and the Butler family has spent years testing myriad combinations to find those that are most successful to offer to its customers. David Butler says that, while his company offers and/or modifies virtually any original or aftermarket casting presently available, he feels that BP's Wide Port Edelbrock cylinder head is among the very best for serious performance applications.
"We spent a lot of time on the dyno and dragstrip searching for a highly-efficient intake port, and began marketing our Wide Port package in the late '90s. At the time, the castings were all hand-ported, but we're now using a CNC mill to perform most of the port work. The consistency of Edelbrock's casting has always been great, and once we developed our CNC program, only a small amount of hand-finishing was required."

Butler says that the Wide Port starts life as a semi-machined 72-cc Edelbrock casting that's prepared similarly to the hand-ported offering featured previously. "We keep plenty of machined castings in stock and build to order. Its combustion chambers are polished, and oil return holes are modified to promote quicker drain back. We then finish and assemble it to match each customer's specific application."

Base price for the bolt-on Wide Port package begins at $3,595. That includes 2.19/1.77-inch stainless-steel valves, solid roller valvesprings, and Comp Cams retainers and valve locks. The intake port measures around 275 cc, and airflow peaks near 370 cfm at 0.750-inch, at 28 inches of pressure. The exhaust port flows roughly 70 percent of that value.

Because of added intake port width, the Wide Port requires the use of a few non-conventional components-all of which BP stocks. "The required solid roller lifters are offset 0.18-inch, and we suggest an offset T&D rocker shaft system. Aftermarket intake manifold choice is presently limited to our custom sheetmetal or a Wide Port-modified Edelbrock Victor, BOP Engineering's cast-aluminum four-barrel, and Wenzler's Gutsram," he adds.

Even after polishing, combustion chamber volume remains around 72 ccs. "We can mill the deck surface to reduce chamber volume into the mid 60s, or enlarge the existing chamber up to about 80 ccs," Butler says. Since Edelbrock isn't presently offering a semi-machined version of its 87-cc casting, BP doesn't mass-market a larger-chamber Wide Port. Butler adds, however, that if a customer is willing to accept the added expense of modifying an 87-cc casting, the company can certainly create a large-chamber Wide Port, too. 2016 Update:Heads are now available in 72cc, 87cc, and now 95cc CNC round chamber for power adder application

Butler feels his company's Wide Port casting is very versatile. "We suggest a minimum bore diameter of 4.15 inches, and have used it in applications that range from high-performance-street to full-race. It's most popular on engines that displace at least 467ci, and we've been very satisfied with the results. We're seeing around 800 hp at 6,500 to 6,800 rpm from a typical pump-gas 500ci engine with 11:1 compression, and a Victor intake manifold. Add a tunnel port intake and compression that's near 15:1, and we're consistently seeing over 900 hp at 7,000 rpm."