all those Engines are running Rhoades Hydraulic Flat Tappet Lifters
Have you experimented with different preloads or are you your running them lashed?
Chris has on some of our Tests ... but i admit i'm typing down Info into WinDyn as Chris says the changes he makes
and sometimes in a hurry to do so ... some of the Info could be misunderstanding on the Hot Lash settings that are on the Dyno sheets ??
i'll ask/clarify Wednesday when we Dyno again
EDIT : i do a few Dyno tests with the Air Turbine to see if we are "Floating Valves "
Lashing Hydraulic Lifters tests shows up on the Air Turbine also