Originally Posted by fastball

OHC and DOHC engines are more efficient and run smoother than pushrod designs. Talk to any mechanical engineer. There is a good deal of energy used (read fuel economy lost ) in the transfer from the cam through the rods up to the valves to open and close them. It is much more of an efficient design to run the valves directly off the cam. A pushrod design is simple and reliable, but if done right, OHC is just as if not more reliable than a pushrod. And the efficiency equation can either yield better fuel economy or more hp, depending on how the rest of the engine is tuned.

And I know people don't care about fuel economy with a Corvette. So, to increase performance, just bore it and stroke it to 6.0 liters (which the C6 is now).