The orifice that leads from the oil pump to the lifter gallery (arrow) is opened up to 1/2-inch to increase volume and pressure.
Czarnota opened up the passage leading to the oil filter (arrow) to 9/16-inch.
It is very wise to replace the poor-performing rope-style timing cover main seal with a neoprene unit from Fel Pro (PN NU 15200). Since the stocker is a stake style piece, the stakes must be ground down to ensure a tight fit.
This Duttweiler-modified intercooler is an excellent cost-effective option, when little increase in boost pressure is planned.
In the early days of intercooled Buicks, Kenny Duttweiler discovered the importance of the outlet neck of the stock chiller by running an intercooler backwards. The improvement led to the development of a cast replacement neck.
Rebuild time is also an excellent opportunity to upgrade to a second-generation crank sensor, which is more durable and reliable than the original.