“Spintron machines and computer-aided programming, combined with improved materials and manufacturing have given us the tools to build engines with more camshaft lift, greater ramp rates, and at the same time allowed engines to maintain valvetrain stability, even when engine speed exceeds 10,000 rpm.”Ī typical cam-in-block engine uses lifters, pushrods, rocker arms, valve springs, valve spring retainers and retainer locks. “Fortunately, the industry has worked hard to improve valvetrain performance,” adds Jesel’s Rob Remesi. Those components are developed under some geometric constraints to produce the desired motion of the valve, and never the other way around.” Please remember we are far more concerned with valve motion than anything on the cam and lifter side. If you ever need sleep, look up the mathematics of exactly how they work. “In mathematics and physics, this relationship is known as a coordinate transformation and often solved with Laplace Transforms. You are calculating a lifter position at every cam degree that is required to convert the linear position of the valve from its rest on the seat to the angular position of the camshaft as it is driven at half crank speed. Goodwin continues, “From looking at valve motion design, the role of the lifter becomes clear. Knowing the required tappet motion, the cam profile is calculated using the theory of envelopes to determine the requisite cam surface.” After you develop the lift, velocity, acceleration, and jerk curves you want for an application, then you work backwards though the rocker arm, to the pushrod, and back to the required tappet motion to produce that valve motion. “Maybe that was the way things were done in the 1970s and ’80s, but from the late 1990s through today we always start by designing valve motion. “We really do not design ‘camshaft profiles,’” says Comp’s Trent Goodwin. To get a better look at today’s lifter technology, we turned to the experts at Comp Cams and Jesel Valvetrain. Hydraulic lifters use zero valve lash so they are low maintenance and operation is quiet. It uses oil to cushion the pushrod and valvetrain. This is a typical hydraulic flat-tappet lifter. The key, then, is to select the best parts for your application. It’s hard to be consistent or win races when your engine encounters valve float, dropped valves, or valve-to-piston contact. Additionally, poor parts selection or improper setup can rob power and/or lead to a costly and catastrophic failure. Whenever moving to a bigger cam and/or higher RPM, special consideration must be given to the lifters, pushrods, rockers, valve springs, retainers, and keepers. If the valvetrain is not operating in a controlled manner (meaning you have valve float or bounce), performance will suffer.
When horsepower increases are discussed, the first thought is often the induction system, but in order to reap the maximum benefits of ported head and intake combinations, or forced induction, the valvetrain must be up to the task. There are dozens of components that must work in harmony to produce the efficient cylinder filling, and combustion, which will ultimately deliver maximum thrust on the pistons. That’s just what our Speedmaster™ guideplate sets do, they are made from 5140 Chromoly steel, nitrided and black oxide coated for corrosion and wear resistance.Preparing an engine to achieve maximum performance requires careful consideration in parts selection, machining and assembly. You need guideplates to keep your pushrods from deflecting under high-rpm conditions.Superchargers, Centrifugal Style Head Units.Throttle Return Spring and Bracket Kits.Carburetor Metering Blocks, Replacement.Air Filter Assembly Wingnuts & Fasteners.