Speed Flow Technology

Dart’s method of developing products for racers is a process that Dart founder and president Richard Maskin calls “Speed Flow Technology.”

“We’ve invested heavily in both equipment and people to give Dart the capabilities to produce winning parts for racers,” Maskin explains. “Speed Flow Technology is an integrated approach that allows us to develop new products quickly and efficiently. Except for pouring the raw castings, we do everything in-house, from design and development to manufacturing, inspection and shipping. This ensures that we produce parts that meet our standards for quality and performance.”

One of the breakthroughs in cylinder head development is wet-flow testing. Although dry flow benches are now commonplace in engine shops, conventional dry benches simply can’t duplicate the conditions that exist inside the ports when fuel is introduced to the airstream.

The centerpiece of Dart’s Speed Flow Technology cylinder head development program is a massive wet-flow bench. Unlike dry benches that are converted to wet-flow testing with add-on kits, Dart’s bench is a dedicated wet-flow design. In wet-flow testing, liquid is injected into the airstream to simulate the behavior of atomized fuel in the engine.

“We’ve learned through experience that if a change in port design increases dry airflow without a corresponding increase in wet-flow numbers, then the change usually isn’t for the better,” says Maskin. “On the other hand, if a change improves both dry flow and wet-flow, then it’s usually worthwhile to test on the dyno and the race track, because often it will show an improvement in performance as well.”

Dart’s Spintron is another essential tool in engine development. A Spintron resembles a dynamometer, but it has an electric motor that spins the test engine’s valvetrain at high speed. Outfitted with lasers and high-speed video cameras, the Spintron gives Dart technicians the ability to observe and analyze valvetrain components at high rpm. Many of the performance gains made in Pro Stock in 2004 were the direct result of increases in engine speed due to lighter, stiffer and more stable valvetrain components developed on the Spintron.

Technology continues to transform the way cylinder heads are designed and manufactured. Dart employs the latest computer-aided design and manufacturing (CAD/CAM) techniques. After a new design is developed and tested, a digital coordinate measuring machine (CMM) creates an electronic file of the complex contours. This file then becomes a template for the computer numeric control machining centers (CNC) that duplicate the shapes in production Dart heads with uncanny precision.

Machines haven’t made humans obsolete, however. It still requires a craftsman to develop the intricate port shapes and complex combustion chamber contours. Tony McAfee is responsible for the ports in many Dart cylinder heads. After a runner shape is finalized, Dart’s digital machinery duplicates the design.

The next phase in Speed Flow Technology is testing – in the dyno cell and on the race track. Dart’s in-house engine shop builds and tests dozens of engines every season. Maskin and driver Rickie Smith campaigned Dart’s Pro Stock Cavalier on the NHRA Powerade Drag Racing Series, providing real-world results that validate the high-tech approach. Maskin also talks daily with top engine builders and racers to get their ideas and feedback.

The final step is manufacturing. Dart uses massive computer-controlled machining centers that can machine eight cylinder heads at a time. These immense 50-horsepower Makino machines run 24 hours a day, seven days a week at Dart’s manufacturing facility in Melvindale, Michigan, to meet the demand for Dart products.

“Racing gives us reasons to develop our technology and capabilities,” says Maskin. “Wet-flow testing, our Spintron valvetrain tester, and empirical testing set Dart apart from the competition. Our Pro Stock program and our daily interaction with professional engine builders allow us to stay abreast of developments and to continue to evolve Dart products. We’ve made the commitment, bought the equipment and hired the best people to keep Dart ahead of the competition. We’re racers, and the bottom line is that we come to work every day and have fun.”

Dart's Spintron Machine

CAD Design Software