Speedmaster | August 2016

Oval Track Cylinder Heads

by Performance Racing Industry

Despite the limitations imposed by sanctions large and small, cylinder heads for oval track racing continue to make strides in efficiency and durability, producing more power with greater reliability. New designs are few, but significant gains are many; this is a game of incremental increase. “In any form of racing,” commented David McCarver of RHS, Memphis, Tennessee, “people will always try to improve on what they have. If you race, you want the best cylinder head allowed for your engine to make as much torque and power as possible.” “Every year power levels improve slightly,” noted Mark Fretz of Brodix, Mena, Arkansas, “as the engine builders evolve their programs, and the head porters find new ways to tweak what’s already there.” Smitty Smith of Edelbrock in Torrance, California, agreed with this assessment. “We’ve been refining our current cylinder head designs to improve performance— even more so in the last couple of years—to stay ahead of our competition, to keep up with the racers’ demands, and, most importantly, to increase the horsepower output of their existing engines, as they are all trying to be faster and better than the next racer they are running against.” “Power levels have gone up for a variety of reasons,” added Richard Maskin of Dart Machinery, Troy, Michigan. “The engines have gotten better because the crankshafts are better, the piston rings are better, everything is better”—and that, of course, includes the cylinder heads. Also, “headers change, manifolds change, so we’re always improving and adapting our ports. And so the same engine today is probably making 100 more horsepower than it did just five or 10 years ago.” Meanwhile, sales of new parts remain strong and growing. “We are fortunate to report an increase in all circle track segments, across the board,” reported Jay Verduzco of Speedmaster, Rialto, California. “Circle track is a big part of our business, and will continue to grow.”

Open Heads Rule

New designs—as well as significant improvements to old favorites—come about through a combination of cutting-edge technology and decades of racing experience. “Every time we design a new cylinder head we learn more about producing velocity and swirl in the combustion process,” said Smith. “Our engineers use the latest R&D software to create new cylinder heads in the computer, which they can also test with Computational Fluid Dynamics (CFD) software. Then they can create actual prototypes in-house using our Fortus 400 3D printer, and test the 3D-printed part on our SuperFlow SF-1040 flow bench. They can modify the 3D part, adding or removing material; and then laser scan the result to transfer back to the computer and re-print another part— with all the changes determined by testing already implemented. And all of this can be done before we invest in the tooling to make a finished part out of aluminum.” Of course, the biggest opportunities for change lay in the handful of elite, openhead- rules classes. “The larger cylinder head companies are, and will, continue to design and/or redesign their heads based on market demand—especially in the oval track segment,” noted McCarver. “While sanctioning body rules do usuallydictate what type of head can be used—for example, a 23-degree valve angle for many small block Chevrolets—the professional series such as the World of Outlaws (WoO) sprints and late models, and the Lucas Oil Late Model Dirt Series, mostly maintain open head rules. So these drivers and engine builders will continue to search for more power and performance.” “The newest heads for circle track are going to be engineered for the 4.500-inchbore spacing engines used in the Lucas Oil and World of Outlaws dirt late model series,” added Fretz. “We offer those in several different valve angles—10 degrees, 11 degrees, and 13 degrees”—all of which have enjoyed continuing success.Tim R. Torrecarion of Air Flow Research (AFR) in Valencia, California, anticipates a fourth-quarter release of a race specific 18-degree Magnum head “that we expect will be well-received by those looking for an alternative to a Big Chief or SR20 head.” Jeff Jones of 1 Way Technologies in Washington, Indiana, cited northeastern big block modifieds as well as the professional WoO and Lucas Oil series as markets “where we have a larger opportunity for freely creative cylinder head design. We are always evaluating the cross-sectional area of ports, wet flow patterns, and mass airflow, and swirl in the development of new cylinder heads.”