Originally Posted by Larry from Endyn

Regardless of piston ring condition, all Honda VTEC engines all suffer from excessive crankcase pressure at high power and RPM levels. This is caused by extreme piston speed, long camshaft timing events, and a PCV system that is completely inadequate at high throttle angles and low manifold vacuum levels.

Many of today's large displacement B series engines are based on new blocks where Honda deleted the breathing "can" (on the rear of the block), causing these engines really suffer from extreme crankcase pressure (frequently high enough to rush past the seals, blowing the spark plug wires off the plugs.) Pressures like these cause oil and other contaminates to severely degrade the quality of the mixture in the cylinders, reducing power and greatly increasing the possibility of detonation.