Proibe Most of the article is basic true to a certain point. Leak down test is not going to show you if you have bad valve guides unless the valves are off centered on the valve seats. Unless you have the valve cover pulled and have a bad valve you might not see the air leaking though the valve stem seal and know how good or bad the valve guides are. This is where the machinist shines with knowing clearances. Tigher rod and main clearances will raise
oil pressure. Cross drilling cranks years ago was used to help extending the life of motors at high rpms. Problem with this is at idle you have almost no
oil pressure. They have figured out that on some cranks to relocate the oiling holes for the rods. This help stop the metal to metal contact on the exhaust cycle. Bet you didn't know that the exhaust cycle is the worst of the 4 cycles for stress on the motor. Blue printing a motor takes time and good equipment. Over all the motor should last longer, have better power, less vibration and just run easier. Gald your motor and car are ok. Rick L.