At a time when most aftermarket speed equipment focused on flathead Fords and early V8s, Eddie Edmunds quietly offered performance parts for engines that were never meant to race—Pontiac’s smooth, torque-rich Straight Eight among them. Best known for its finned aluminum cylinder head, Edmunds gave Silver Streak owners a rare opportunity to improve performance while staying true to the engine’s original character. Today, surviving Edmunds Straight Eight components are scarce, highly sought after, and widely regarded as the holy grail of period-correct speed equipment for Pontiac’s straight eight.
Eddie Edmunds: The Mind Behind the Metal
Eddie Edmunds was a hands-on mechanic and fabricator who came up during the early days of American speed equipment, long before the aftermarket became an industry. After working on dirt track cars in the 1930s, he began experimenting with aluminum intake manifolds and cylinder heads, first in the Pacific Northwest and later in Southern California. His move to Los Angeles proved pivotal—placing him near foundries, mold makers, and a growing car culture that was hungry for performance. Edmunds didn’t build parts for racers alone; his goal was simple and practical: give everyday drivers a way to wake up the engines they already owned.
Under the banner of Edmunds Custom, the company offered an unusually broad lineup of speed parts, producing intakes and aluminum heads for engines most manufacturers ignored. Flathead V8s were only part of the story—Edmunds made equipment for inline engines, luxury cars, and workaday sedans alike, including Pontiac’s Straight Eight. The castings were distinctive, the designs evolved constantly, and production numbers were never large, which only adds to their mystique today. While the company’s run was relatively short, Edmunds’ impact was lasting, leaving behind some of the most recognizable and sought-after period speed equipment of the postwar era.
A Rare Piece of Pontiac Speed Equipment
Today, original Edmunds aluminum heads for the Pontiac Straight Eight are incredibly difficult to find. Unlike more popular flathead V8 applications, Pontiac straight eight speed parts were produced in small numbers and were often installed on everyday cars rather than preserved as collectibles. Some say they’re made out of “unobtainium,” simply because so few exist. Many were lost to scrap yards, corrosion, or decades of hard use. As a result, surviving examples surface very occasionally—often damaged or already spoken for among dedicated early Pontiac fans. Finding a complete, usable Edmunds head for a Silver Streak engine now requires patience, persistence, and a bit of luck, which has only cemented its reputation as one of the true “holy grail” speed parts for Pontiac straight-eight enthusiasts.
Design, Function, and Performance
From a functional standpoint, the Edmunds aluminum head offered several meaningful advantages over the factory cast-iron piece. Most Pontiac Straight Eight engines left the factory with compression ratios in the 6.5:1 to 7.0:1 range, prioritizing smoothness and longevity over outright performance. The Edmunds head typically bumped compression by roughly three-quarters to a full point.
Being cast in aluminum, the head also shed a significant amount of weight from the top of the engine while dissipating heat more efficiently than the stock iron head, helping the engine run cooler and more consistently. Visually, it was just as much of an upgrade—its finned design and hand-carved EDMUNDS lettering instantly set it apart, transforming the otherwise understated straight-eight into something that looked purpose-built. Importantly, the head retained stock valve geometry and overall compatibility, making it a true bolt-on performance and appearance upgrade for Pontiac owners of the era.
The Ones That Survived
Today, only a handful of Edmunds aluminum heads for the Pontiac Straight Eight are known to still exist, and even fewer are confirmed in private hands. As of now, only two owners are publicly known within the Pontiac community—Jace in Michigan, who will be using it in his 1951 Pontiac Super Deluxe Catalina and Joe in Pennsylvania, who has it powering his 1953 Pontiac Custom Catalina. Both are early Pontiac enthusiasts who understand exactly what these pieces represent. These heads are not shelf decorations or casual collectibles; they are deeply appreciated artifacts from a time when speed equipment for Pontiac’s inline engines was almost nonexistent.
Adding to the mystery, there are persistent rumors of a large private car collection in Washington State that may contain two additional Edmunds heads for Pontiac straight eights. According to those familiar with the collection, the cars—and the parts with them—belonged to a recently deceased car enthusiast, and the family has chosen not to sell anything. Whether those heads will ever resurface remains unknown. For now, they exist only as stories passed quietly among enthusiasts—fitting for a speed part that has spent most of its life hidden in plain sight.
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