[Purdy Swoft]

Adjustable valve lifters or model B lifters that are longer than model A lifters will be required If you use a B cam or a cam with more lift. The reason is that original model A lifters will be too short unless you use modern valves. Bigger valves will help but will be shrouded on the manifold side and will probably need some relief work on the head that will in turn lower the compression.