Edelbrock's newest offering...
Edelbrock's newest offering for the Pontiac V-8 is its Performer D-port cylinder head, which is full of modern technology. Based on an original '69 No. 62 casting, it will accept any and all factory hardware, including original cast-iron exhaust manifolds. The high-flow casting is an excellent choice for smog-legal performance engines. Though this particular example is a prototype, we're told it closely represents the unit that is expected to be in production by the time you read this.
Even though the last Pontiac V-8 was produced in March 1981, for fans of the legendary engine, it's still a great time to be a Pontiac hobbyist. Each issue of HPP contains a Product Preview department, in which new products intended to improve your car's appearance, performance, or economy are displayed. Every once in a while we're able to feature something as exciting as a new Pontiac V-8 cylinder head-and it's that time again!
Though other aftermarket companies produced new cast-aluminum Pontiac cylinder heads before Edelbrock, it was the first to produce them on a large scale. It developed and introduced its Performer RPM in the mid '90s as a modern replacement for the valuable R/A-IV castings, which were highly sought by racers for their small combustion chambers and excellent airflow potential.
The Performer RPM cylinder head was capable of flowing 280 cfm out of the box, and more than 300 cfm with a bit of port work. It has proven a successful venture for Edelbrock; according to the company, it continues to sell very well.
Since its introduction, Edelbrock has been flooded with customer requests for a modern D-port casting. The company has answered with its new Performer D-port cylinder head-and HPP is the first to bring it to you. Follow along as we provide you with a first look at Edelbrock's prototype casting and learn of its developmental insights from key company insiders.
The Performer D-port features...
The Performer D-port features a high-flow intake port that measures 185 cc yet flows 270 cfm. It accepts any traditional '65-'79 Pontiac intake manifold. Port entrance is only slightly taller than an original Pontiac D-port, and requires an Edelbrock No. 7280, a Fel-Pro No. 1233, or an equivalent intake-manifold gasket set.
"Our Performer RPM casting was introduced about 15 years ago," says Smitty Smith, Edelbrock's technical sales coordinator. "We immediately began receiving requests for a D-port casting as soon as the round-port-based head came out. Since there are many D-port owners out there, we planned on producing a new casting for that market segment years ago, but various other projects kept pushing it back."
"We took the typical Edelbrock approach toward development of the new cylinder head," says Ray Garcia, Edelbrock's technical sales representative and resident Pontiac fanatic. "Our goal was to produce a high-quality D-port that would perform well and fill a large market void." To accomplish this, Edelbrock combined its cast-aluminum Performer RPM with a well-ported original Pontiac D-port cylinder head to create its newest entry for Pontiac hobbyists-the cast-aluminum Performer D-port.
"My own '69 No. 62 cylinder heads were used as the basis to develop the Performer D-port," Garcia states. "The No. 62s had been ported by R&R Automotive Engineering in Covina, California, and intake airflow peaked at 245 to 250 cfm at 28 inches of pressure, and 165 cfm exhaust. We planned to adapt what we learned developing the Performer RPM intake port to increase intake airflow beyond that for even greater performance."
In today's hobby, with the availability of stroker kits and/or large-bore aftermarket blocks, Garcia finds that engines are always getting larger, not smaller.
Like the Performer RPM, the...
Like the Performer RPM, the new Performer D-port deck surface is 5/8-inch thick for optimal durability and maximum gasket retention. The casting requires the use of Edelbrock's No. 8561 head-bolt kit for installation.
"Many feel the 215cc intake port of our Performer RPM is too large for the street, but we've found that the long connecting rod and big crankshaft throw associated with the Pontiac V-8 tend to make them less sensitive to port volume. The RPM is a great head for street engines, and I pushed for a large intake port when developing the Performer D-port-one much like that used in our Performer RPM."
He continues, "We determined that a majority of buyers would be installing the Performer D-port on street-driven 389, 400, and 455-inch engines, however, and that some of those would need to be emissions-legal. We ultimately decided on an intake port with less volume than the Performer RPM, which tends to promote port velocity and can improve low-speed throttle response, while remaining 50-state emissions compliant."
Garcia's No. 62 casting was used to gather all of the external characteristics and nominal dimensions for the Performer D-port. The basic deck and intake flange architecture, and cooling jacket placement was borrowed from the Performer RPM casting. The high-flow RPM intake port was reduced slightly to fit the Performer D-port package. The result was a compact intake port that measures 185 cc and still peaks at 270 cfm with plenty of wall material for future growth.