Engine crane lift professional#

Steve decided that rather than go for it all at once, we would begin at 7,000 rpm and work our way up. With the Westech 355ci small-block assembled, it was time to start twisting up the rpm. If the springs, retainers, valves, rocker arms, and pushrods are properly matched, valvetrain separation should be an extremely rare occurrence. This again reinforces the point of a systems approach to a high-rpm valvetrain. Valvetrain separation occurs most often not through the fault of the lifter but rather either poor valvetrain harmonics or by any number of potential problems, such as flexing pushrods, weak valvesprings, heavy valvetrain components, or perhaps a dozen other potential problems. This could be enough to hold the valve open, which would be instantly followed by a dramatic loss of power. When this occurs, engine oil pressure forces the small piston upward against the snap ring, eliminating the amount of lifter preload. In this case, at some rpm point, valvetrain separation occurs due to a loss of control of the valve by the spring, causing a gap to open between the rocker-arm tip and the top of the valve stem. The other problem area is the exact opposite of lifter pump-down-the dreaded lifter pump-up.

Engine crane lift professional#

Most professional engine builders would recommend at least a shaft rocker system, along with custom, 38-inch-diameter pushrods to achieve even greater stiffness. The amazing part is that it did it using street version 516-, 0.080-inch-wall pushrods and a stud-mounted rocker system. This 8,500-rpm hydraulic roller lifter 355ci small-block is stout not just because it was able to achieve a very stable rpm curve. The key to a successful high-rpm hydraulic roller valvetrain, according to Knight, is a combination of lightweight and high-strength components. This is a machine developed by Bob Fox, which allows valvetrain developers to test components like cam lobe profiles, lifters, valvesprings, retainers, valve locks, pushrods, and rocker arms for durability and compatibility. If you are serious about valvetrain development, you either own or have access to a Spintron. Crane has put major research effort into matching valvetrain components that they know will withstand these high-rpm ventures without failure-effectively, a system's approach to the valvetrain. Knight emphasized that professionally matched components that are proven to work well together is key. We spoke at length to Chase Knight at Crane Cams about these 8,500-rpm small-block lifters to understand why this system works so well. We've grown accustomed to seeing NASCAR small-blocks spin to 9,000-plus rpm on television, but that doesn't mean that your stock small-block will live at those speeds. RPM is the great determiner in terms of engine durability. Therefore, the long-stroke piston must travel much faster and accelerate away from both TDC and BDC much quicker at this same speed. A 3.00-inch-stroke 302 small-block Chevy piston travels a much shorter distance than a 4.00-inch stroke small-block at the same engine speed. Stroke obviously plays a part in this equation, as well, since the G-loads imparted on a piston and rod assembly at a given rpm are directly affected by stroke. This means a high-quality forged crank, forged pistons, and stout connecting rods. So let's start this discussion with a qualifier that even with a killer 8,500-rpm valvetrain, you still must have an extremely reliable rotating assembly to be able to withstand these engine speeds. Don't we already have entire catalogs of mechanical roller camshafts and stiff springs that will achieve mega rpm? The obvious answer is an unqualified yes. The team of Westech Performance's Steve Brul and Crane Cams' Chase Knight collaborated to assemble a small-block Chevy that we would spin to 8,500 rpm, just to show that it could be done. So when the guys at Crane claimed they had a hydraulic roller lifter that would live at 8,000-plus rpm, we were interested. But in order to reliably achieve those stratospheric engine speeds, conventional wisdom holds that you have to run mechanical roller lifters, monster valvespring pressures, and expensive shaft-mount rocker systems-and those are just the valvetrain pieces. If the engine can make good torque at a higher engine speed, it will make more horsepower. But for most street-car enthusiasts, engine speeds above 6,500 rpm (and certainly beyond 7,500) might as well be a bench-racing fantasy. For anyone who appreciates internal-combustion engines and horsepower, a race engine spinning at high rpm is hypnotic. There are very few sounds sweeter to a gearhead than a small-block spinning past 8,000 rpm.