[Alan Roehrich]

Tool steel lifters are fine on cast cores. You simply can't run DLC coated lifters on cast cores.

Remember that break in is absolutely critical, you need to be sure the engine can start instantly, go to 2,000 to 3,000 RPM immediately, and stay there for at least 30 minutes. Pre oil the engine, make absolutely certain that you generate good oil pressure, and do not stop until oil is present through the pushrod at every single rocker arm. Be wary of any oiling issues, if it seems like it is taking too long to get oil to the rocker arms, it probably is. You should not exceed 250 pounds OPEN pressure during BREAK IN, 200 pounds is fine, but do not exceed 3,000 RPM with lower than race ready spring pressure. Use a premium quality break in oil, 30W is the minimum viscosity. Make sure that all the lifters are rotating when you're running the engine, you'll know because if the pushrods are rotating, the lifters are, and if the pushrods are not rotating, the lifters are not, and failure is imminent. Several rocker arm companies make break in rocker arms with low ratios. They're worth it.