Unlike any other popular overhead valve engine, the ’53 to ’64 Buick engines had a rocker arrangement where the rockers met the pushrods on the outboard side of the head and the valves on the inboard side. Viewed from the side, the valve stem crossed the pushrod. This had several advantages: The valve placement was near the center of the head (like a Hemi), the engine was narrow for its displacement, and the engine had a lot of torque. Buick was so proud of the torque numbers that they used them to identify the engine instead of horsepower or displacement. The 340 horsepower 425 was called a Wildcat 465. The 360 horsepower two four barrel version was dubbed Super Wildcat 465.
However, the valve arrangement also had disadvantages. One of them is that the valve placement necessitated very small valves for the engine displacement, giving rise to the derisive term “Nailhead” to describe the engine. The rocker arms also have an angular configuration in two dimensions; viewed from the side and from above. There is very little clearance between the rocker arm and the valve spring assembly. In addition, the exhaust passages are long and tortuous, making these engines harder to cool than most.
Kenne-Bell used to be the go-to company for performance Buick parts. (They have since switched to Mustangs because very few performance Buicks are being built nowadays.)
Kenne-Bell valve springs for Buicks are larger in outside diameter than original Buick springs. This extra diameter exacerbates the rocker to spring clearance problem. The rocker arms must be hand filed to provide at least .030 clearance.
After the rocker arms were filed, the engine noise disappeared.
On March 16, 2001 the car was loaded on Passport Transport and shipped to Denver where I lived at that time. The car had spent four years and one day at Rustic.
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