Not many cars have engines this big, but the ones that do usually generate well over 300 horsepower. The intake and exhaust are tuned and tested to provide a boost at certain engine speeds. They are also designed to have very low restriction, and there are no mufflers or catalytic converters to slow the exhaust down either. They have high intensity programmable ignition systems so the spark timing can be customized to provide the most possible power. All of the subsystems like coolant pumps, oil pumps, steering pumps and alternators are designed to run at sustained high speeds and temperatures.
Cylinders are bored to more exacting tolerances than street cars.
The crankshafts and other rotating parts are balanced. Making sure that the parts are as close to their exact dimensions as possible helps the engine achieve its maximum potential power and also helps reduce wear. If parts are too big or small, power can be lost due to extra friction or pressure leakage through bigger than necessary gaps. The engine is then inspected. The filters are checked for excess metal shavings to make sure no abnormal wear is taking place.