To answer your question crxtacy, the only part of the engine that would need to handle high reving would be the cylinder walls, pistons and the crank. You see, the longer your rods are, the more stress you put on your cylinder walls because your crank never pushes the piston strait up. The crank moves in a circle and the end of the rod that is connected to the crank is what connects the power from the piston to the crank. The crank never pushes strait up... ever. The only time they are all alligned are when the piston is at its peak height or at the bottom of its decend.
I guess you can say that the rod is what converts the up and down power into a circular motion which makes your motor turn. I believe rotary is more effective at the transer.
So basicly what I have learned through searching. No help from other people on the board. *cough* andera *cough* Is that shorter engines are the only good engines for reving high simply because the R/S ratio is better. The piston doesn't have to move up or down as far therefor you can get more RPM's safer.
But because the rods are so short, you can say goodbye to your torque. This is a trick of motorcycles. Especially sport bikes. They are made to rev high because they need more horses than torque to push those 400lb. monsters. Cars need more torque to push their weight. Thats why they can get away with it.
So indi cars are made to rev high because they are lightweight and aerodynamic. They can do fine with a little less torque. But racing with heavier cars like NASCAR, they CAN rev high, but not as high. They need that precious torque to move them along. They are not as aerodynamic so thats where drafting comes in.
So that said... some ricers think more horsepower is more important than torque... WELL, it WOULD be if your car was about 800 pounds lighter! Building your engines to rev higher WILL give you more horses, but will it make you go faster? Depends on how badly your car needed that torque.
THATS why you plan ahead. Hey cool, I learned something new today.