Found this in the Nov. 03 Motor Trend:
"Beware, Dodge Viper and Ford GT. The 2006 C6 Corvette Z06's 6.3-liter Gen-IV small-block pushrod V-8 features 24 valves and makes 500 horses at 7000 rpm. The Gen IV is the featured engine using a new GM Powertrain technology: a three-valve/cylinder pushrod valvetrain, which the automaker also will use in some High Value V-6's. The C6's small-block can grow to 7.0 liters and rev to 8000 rpm. The new design pairs intake valves side by side; they're operated by a forked rocker arm. The exhaust valve sits on the opposite side of the combustion chamber, with a centrally located spark plug in between. The Gen IV flows more air through its dual intake ports, and the intake and exhaust ports are more widely separated for less heat transfer from the exhaust to the intake charge. The extra horses work well with the Displacement on Demand system that appears with the Gen-IV V-6 and High value V-6's- more power means more opportunity for the engine to idle half its cylinders. Look for the deeper-breathing heads and associated upgrades in the 2005 model year."

:o Wow... I want one! Sounds like an awesome engine- a pushrod production V-8 that can rev to 8k?