Budget Rocker choice

mopowers said

Quick question from a bonehead - Has any testing been done to actually quantify what that 30% results in, in term of lost duration/lift, hp (verified on a dyno), etc? At what point does valve train geometry that's not perfect actually become something that's noticeable in the real world?

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30% is actually a little bit of a lowball number. With exception for the Trick Flow heads, the average is probably closer to 40-50 percent.

I have done dyno testing on a small block combo that had a 52% error. It went into severe early valve float, and limited rpm well below the intended shift rpm. After correction, the rpms were clean thru the shift rpm and beyond. We gained another 800 stable rpm, and picked up another 46 horsepower at the shift point. The conventional wisdom would have been to throw more spring on the heads to control the float, but it wasn't necessary. Valve side loading was reduced, which helped save the guides over the long haul. And, the jackhammering effect of being in valve float would have destroyed parts in short order. Oh, and this was a mild hydraulic cammed 9 to 1 CR 360.

While we didn't break anything on that engine, I've seen enough broken rockers, dropped valves, tore up guides etc, to know how critical this is.

Lastly, you're not a bonehead. A bonehead refuses to think or learn anything new.