Camshaft And Valvetrain Technology Insight - On The Lobe's Edge

Crane Cams
Next up-and remember, we went about his alphabetically-was a call to another of the valvetrain gurus we've been known to call when we need something cleared up for us, Crane Cams' Chase Knight. In answer to our question about what's new at Crane, Knight quipped, "It depends on your definition of new. The LS family is showing definite growth." Point taken-the platform is now more than 10 years old, but that's still new by traditional small-block standards. "We're continuously working on cams for the LS1 and LS2," he said, "and also the LSx, which usually prefers grinds with a wider lobe separation angle. We're adding more grinds in both hydraulic and solid rollers, so we have the right application for people."

Among the new selections are the Chevrolet LS Street/Strip Series and the Big-Inch-Wide Separation hydraulic roller cams, designed specifically to produce max power from big-cube LS motors while maintaining good street manners. And for those who find the LS7 lacking, Crane developed the LS7 Series Hydraulic Camshaft line with the emphasis on "extreme intake air flow."

Both cam varieties share some extra technology from Crane. For one, they use what the company calls Rapid Ramp lobes. The idea, of course, is to create that Holy Grail of power under the curve again: High-performance matched with drivability. The new 'sticks, which use a 55mm core, are de rigueur for LSx engines and are also gun-drilled, preserving the strength of the greater core while losing some unwanted weight. The bottom line is that Crane is adding more grinds in both hydraulic and solid roller so that everyone can come up with the right application.

More new components Knight clued us into are the new small-block and big-block Ultra Pro hydraulic lifters and Ultra Pro mechanical lifters. Both versions have an 8620 steel precision body that's been precision-machined, heat-treated, and micro-ground, and the hydraulics are even leakdown tested. According to Crane, these lifters are made for high-rpm, high-valve-spring-pressure applications. Ditto the Ultra Pro mechanical lifters, which use a "four-column" design that's said to reduce weight while maintaining strength and torsional rigidity. They're also heat-treated, have micro-polished needle bearings, and are made to have a lower reciprocating weight from increased rpm potential.

And if you want that kind of performance for your LS motor, don't fret-new Ultra Pro mechanical lifters are coming for LSx engines as well. These spring-loaded lifters will feature a tie-bar design, making the works stronger and lighter than the standard lifter tray configuration. "This is especially important in high-rpm drag racing actions, where they help enable high lift off a small base circle," Knight told us. "There's a lot of escalation in the Ultra Pro. That 8620 steel body holds its roundness along with gobs of spring pressure."

There's yet another new series of Crane 'sticks, the Rapid Ramp Cams. "They really accelerate valves off the seat, getting more area under the curve," Knight said. "It's very dynamically stable, and easy with the LS, light and strong. A lot of these 'sticks, Knight admitted, are street-performance grinds, especially in hydraulic versions. "More serious street guys," he said, are changing springs, lifters, and rockers. "The LSx daily drivers with broad torque band are quiet-the race guys, noisy. And then dune buggies have a different cam altogether. Then there's the road racing Daytona prototype. They're loud with a narrow upper-rpm band. Specialization is getting to be the name of the game-we've got a hundreds of different grinds, and we've always heavy into it."