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Top Dog: Edelbrock’s SC-1 Drag Race Cylinder Heads
Inside Edelbrock’s Proven SC-1 Drag Race Head
John Urist, Billy Glidden, Tony Bischoff, and Jim Kuntz. These are all engine builders and racers that have won championships with Edelbrock’s legendary SC-1 cylinder head. Matter of fact, Urist won 7 out of 9 NMRA Championships running Edelbrock cylinder heads. His first championship was with our Glidden Victor 15-degree cylinder heads in 2003 and the remaining were done running the Glidden Victor SC-1 cylinder heads! Not much is known about this magical cylinder head outside of the top engine builders in the country, so follow along and get educated!
“The History of the ‘SC-1’ first Ford Racing cup cylinder head was originally produced by Ford Racing and was a derivative of the Ford Yates style cylinder head,” explained Edelbrock’s Technical Sales Coordinator Smitty Smith. “The use was intended for NASCAR but after testing, it was not allowed in the series.” Since a lot of development was put into this cylinder head and needed to be used, it was repurposed for use by Sprint Cars, hence the “SC”. The cylinder head was eventually dropped by Ford Racing.
Back in the late 90’s Dr. Rick Roberts was approached by Billy Glidden to develop a fresh and cutting edge small-block Ford cylinder head. This spawned the original Glidden Victor 15-degree cylinder head. “It was the very first Edelbrock head to have a 15-degree valve angle, explained Smith. “Billy ran these in Hot Street, which was a naturally aspirated class in the NMRA and everyone noticed. The following year, every racecar in Hot Street was running the Glidden Victor 15-degree cylinder head.”
With the large success coming from the new 15-degree head, Dr. Roberts and Billy Glidden went back to work on a new design. “Billy was very instrumental in developing the New Glidden Victor SC-1 cylinder head,” said Smith. What’s the difference between the two heads? In short, the Glidden Victor II cylinder heads are an in-line 11-degree cylinder head, whereas the Glidden Victor SC-1 cylinder head is canted valve arrangement similar to the factory 351 Cleveland heads.
The Glidden Victor SC-1 cylinder head falls under Edelbrock’s Pro-Port raw heads lineup. Effectively a blank canvas for cylinder head specialists, Edelbrock only provides the basic shape of the combustion chambers and runners. From there, heads must be ported and have guides and valve seats installed. Like all our other heads, they are also cast in the USA at the state-of-the-art Edelbrock foundry with extra thick walls to allow for custom CNC porting. In most cases, seats and manganese-bronze valve guides are included, but not installed.
Flow on these cylinder heads may not be easily found as all of the cylinder head porters do not always share how much CFM they flow. “We do know they flow really well and make an incredible amount of horsepower when tuned properly,” explains Smith. “We have heard the intake runners will flow from 440-480+ CFM and the exhaust runners in the high 280s-300+ CFM at 28-inches.”
This is all accomplished with a maximum intake valve size of 2.24-inches with the exhaust valve of 1.64-inches. “The intake valve angle is another reason why this cylinder head is so good, it is 7.3-degrees by 0.3-degrees, and the exhaust valve angle is at 6.88-degrees X 0.55-degrees,” said Smith. Keep in mind that getting the valve angle closer to zero allows the air to travel from the intake manifold to the valve with the least amount of turns; less turning increases speed. “Do not forget this is a small-block Ford cylinder head, where the factory inline valve angle is 20-degrees.”
With a raised port location to reduce the valve angle requires an intake manifold specifically designed for the job. For our job we picked up a PN 2868 that’s designed for 9.5-inch deck height Windsor motors sporting a 4500 series carburetor. “ These manifolds also came from our NASCAR racing program,” explained Smith. “These were originally used for Cup, Nationwide, and the Truck series divisions.”
Also designed for a drag racer in mind, it’s a longer plenum front to rear, which makes the runners more equal length to each other. Our 2868 manifold will actually bolt onto a Glidden Victor II and the Glidden Victor SC-1. So if you’re looking to make maximum horsepower for either boosted or naturally aspirated combinations, the Glidden Victor line of Edelbrock cylinder heads should be in your consideration!
What's a HIP process casting?
Many Edelbrock Pro-Port Raw cylinder heads are available with a technique called Hot Isostatic Pressing (HIP). This aerospace process heats raw aluminum castings up to 900-degrees Fahrenheit in a pressurized chamber (up to 30,000 psi) and compresses the casting to remove any trapped gases and internal porosity. The result is an incredibly strong and dense sand casting that has three times the fatigue life and nearly the consistency of billet aluminum.
By the Numbers with Total Engine Airflow
Total Engine Airflow (TEA) was our porter of choice for our heads. We came out with a 390cc intake; 173cc exhaust runner; and a 50cc chamber.
1. The Edelbrock SC-1 cylinder head is one of the baddest small-block Ford heads on the planet. The cylinder head falls under Edelbrock’s Pro-Port raw heads lineup. Effectively a blank canvas for cylinder head specialists, Edelbrock only provides the basic shape of the combustion chambers and runners.
2. The intake valve angle is another reason why this cylinder head is so good, it is 7.3-degrees by 0.3-degrees, and the exhaust valve angle is at 6.88-degrees X 0.55-degrees.
3. All this flow is accomplished with a maximum intake valve size of 2.24-inches with the exhaust valve of 1.64-inches.
4. Cylinder head specialist must install the included guides and seats once the CNC work has been completed.
5. With a raised port location to reduce the valve angle requires an intake manifold specifically designed for the job. For our job we picked up a PN 2868 that’s designed for 9.5-inch deck height Windsor motors sporting a 4500 series carburetor.
6. Just like the Glidden Victor SC-1 cylinder head, there’s plenty of meat left on Edelbrock’s castings for a thorough port job.
7. The runner dividers are pulled back and the end runners are shortened to increase plenum size for more peak horsepower with a larger carburetor.
8. Remember when we talked about how well these heads flowed? Check out the numbers from our heads. A monstrous 470 CFM on the intake and 333 CFM on the exhaust at one-inch of lift!