Four Stroke Design

Valvetrain design software has evolved to a level of accuracy that has enabled us to predict dynamic valve motion with great success. We can design and simulate with great confidence that what we are simulating will be replicated on the Spintron, on the Dyno and on the track. Through the use of the tools in our arsenal we are able to analyze what the Spintron and dyno cannot show. We can visualize the effects of cylinder pressure acting on the valves. The dynamic behavior of the valvetrain is highly dependent on the forces acting on the components. For the worst-case scenario, a NASCAR pushrod engine, the actual exhaust valve opening can be delayed as much as 10-15 crank degrees as a result of the cylinder pressure acting on the valves. The compliance of the pushrod system becomes obvious when you observe this much difference between what you measure on the engine stand vs. what you measure on a firing engine (which requires an expensive high-speed combustion system and application-specific sensors). We can measure the difference in a firing vs. non-firing engine in just a few minutes with confidence that the answer is correct. Why does your hot new cam run perfectly on the Spintron but routinely breaks spring tips at the track? We can tell you. Broken spring tips are a sign when the valvetrain is trying to tell you “It’s only a matter of time before I let you down”! Using valvetrain simulation, we can optimize the design of the valvetrain components to work better together with your existing cam and spring combination or we can start from scratch with a “clean sheet” design. We design valvetrain components based on your goals and your needs. We can also use Engine Simulation as a guide to determine what the recommended lift and duration should be in order to reach our goals.