Edelbrock recently posted a throwback Thursday pic of the company’s first dyno on its Facebook page, prompting EngineLabs to conduct a little more research. We also asked Edelbrock officials to dig a little deeper into the archives for additional shots of the dyno operation.

Vic Edelbrock Sr. was one of the first hot rodders to invest in a dyno, purchasing a Clayton model in 1948. The garage photo shown on this page was taken at Edelbrock’s first shop on North Highland in Hollywood, California. A year later Edelbrock set up shop on the famed “Thunder Alley” in Culver City, a section of Jefferson Blvd. that was home to Isky Cams, Hedman Hedders, Traco Engineering, Dick Gulstrand and even James Garner’s race shop.

Word has it the dyno had a limit of 200 horsepower, but old timers know that ceiling was busted many times, especially since Edelbrock wasn’t shy about testing different fuels. He was notorious for using nitro in sprint cars. But take a close look at that dyno. The controls are right behind the brake. Not sure if anyone would want an engine making more than 200 or 300 horsepower on a dyno where the operator is just inches away from all that energy absorption. Also note the scale weights used to measure the force on the torque arm. Later dynos had the big circular scale that the operator would read. Of course, today’s units are fully computerized, and the dynos are completely isolated in a cell to protect the operators.

In 1957 Edelbrock set a milestone when he pushed a naturally aspirated 265ci Chevy to more than one-horsepower-per-cubic-inch. According to the dyno sheet, the engine was fitted with three Rochester carbs, an Isky camshaft, JE pistons and Hedman headers. The JE pistons mated with the stock heads produced an 11:1 compression ratio, then the heads were milled .050 to bring the CR up to 12.3:1. Edelbrock also polished the crank and rods. At 4,000 rpm the dyno showed 195 horsepower, then at 5,500 rpm the gauge read 265 horsepower. But Edelbrock wasn’t done. Five hundred more rpm and the engine climbed to 275 horsepower before quitting at 6,500 rpm with 279 horsepower. That August 9 test was the first recorded confirmation of a normally aspirated engine producing one horsepower per cubic inch. A note on the dyno chart also says the numbers were observed and not corrected. Room temperature was a breezy 84 degrees, and there was normal atmospheric pressure with the barometer reading 29.2 inches.

The Clayton was used until 1969 when it was sold to Ed Iskenderian. Edelbrock then purchased a Heenan-Froude G490 and Digalog Cellmate CM/2 computer that allowed runs up to 12,000 rpm. Today, Edelbrock’s dyno room in Torrance, California, sports three SuperFlow dynos, including a Powermark that can handle 2,500 horsepower and a pair of SF902 units good for 1,500 horsepower. The shop also has a SuperFlow chassis dyno.