There are several broad rules of thumb that provide clues to whether increasing rocker-arm ratio will prove to be a performance boon with a given engine, cylinder head, and camshaft combination.

It's no secret that adding duration and valve lift helps make power. But besides changing camshafts, there is another way to modify valve events-change the rocker-arm ratio. Ford V-8 rocker ratios-at ...

The debate over the optimum rocker arm ratio to use has dragged on probably since the invention of the pushrod V-8. Even though Chevrolet made the decision easy for us when it engineered the original ...

There are several broad rules of thumb that provide clues to whether increasing rocker-arm ratio will prove to be a performance boon with a given engine, cylinder head, and camshaft combination.