[Alan Roehrich]

Aubrey, those flow numbers are not nearly as low as you think. I'm betting if you sent the heads to the right person to have them done, they'd be even better, especially with the right valves. You have enough cylinder head to make good HP at 6800 RPM with a 0.060" over 409, the biggest problem is probably the intake manifold.

For your cylinder head flow, your cam is too big, especially if it has some sort of wildly aggressive lobe on the intake.

Mark is right, the right headers could reduce the need for all that duration on the exhaust, provided you even need that much now.

With good valvetrain control, 0.055" on the intake and 0.075" on the exhaust is plenty of clearance. With the right cam lobes and the right valvetrain, control should not be a problem.

Working with pushrod length will probably solve some of the problem with longer valves. There's no such thing as "ideal" valvetrain geometry in Stock Eliminator for most engines. The restrictions of the class prevent it. We're not anywhere near ideal with the big blocks, yet we have not had a single valvetrain failure in over 5 years. I think 2006 was the last time we had a valvetrain failure of any kind, and the problem was solved with the correct rocker studs.