With less power available at or near idle rpm due to increased valve duration, it is more difficult for the engine to start moving the vehicle, or keep the vehicle moving. In other words, if typical operating range is from off-idle to 4500 rpm, when duration is increased, you should expect for the engine to start making respectable power at a higher rpm, in a direct relationship, where as the duration increases, so does the lower end of the operating range. This doesn't lend itself well to typical street operating rpm, as it shortens the rpm range where the engine is being efficient. Like any 'bigger' camshaft, lower rpm torque is compromised for mid to upper rpm torque when valve duration is increased. I don't claim smarter than GM engineering, but I wouldn't run that cam in anything.much less a Corvette. This cam is designed for a light vehicle ideally equipped with a manual transmission. I completely disagree with this statement.
