Speedmaster | August 2016 - Oval Track Cylinder Heads, by Performance Racing Industry

Incremental Gains, Measurable Results

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 discipline built on incremental improvement.

"In any form of racing, 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." - David McCarver, RHS, Memphis, Tennessee

"Every year power levels improve slightly, as the engine builders evolve their programs, and the head porters find new ways to tweak what's already there." - Mark Fretz, Brodix, Mena, Arkansas

Smitty Smith of Edelbrock in Torrance, California, noted that the company has been refining its current cylinder head designs to improve performance, with a particular focus over the preceding two years on increasing horsepower output from existing engines.

"Power levels have gone up for a variety of reasons. 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. 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." - Richard Maskin, Dart Machinery, Troy, Michigan

Sales of new parts remained strong across the category. Jay Verduzco of Speedmaster, Rialto, California, reported growth across all circle track segments.

"We are fortunate to report an increase in all circle track segments, across the board. Circle track is a big part of our business, and will continue to grow." - Jay Verduzco, Speedmaster

Open Heads Rule: Where Design Freedom Drives Innovation

New designs and significant improvements to established platforms come through a combination of advanced 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. 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." - Smitty Smith, Edelbrock

The largest opportunities for design advancement exist in elite, open-head-rules classes. Sanctioning body rules typically dictate cylinder head specifications - for example, a 23-degree valve angle for many small-block Chevrolets. However, professional series such as the World of Outlaws (WoO) sprints and late models, and the Lucas Oil Late Model Dirt Series, largely maintain open head rules, giving engine builders room to pursue more power and performance.

"The newest heads for circle track are going to be engineered for the 4.500-inch bore spacing engines used in the Lucas Oil and World of Outlaws dirt late model series. We offer those in several different valve angles - 10 degrees, 11 degrees, and 13 degrees." - Mark Fretz, Brodix

Tim R. Torrecarion of Air Flow Research (AFR) in Valencia, California, noted a planned fourth-quarter release of a race-specific 18-degree Magnum head as an alternative to a Big Chief or SR20 head.

"Northeastern big block modifieds as well as the professional WoO and Lucas Oil series are 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." - Jeff Jones, 1 Way Technologies, Washington, Indiana