Thanks Dag,

Very interesting. Curious if we were to put a hole or two in the header and venting that to atmospheric pressure, if that would disrupt the pressure fronts too much. Before pumps and such, in a way we used to do that whenpressurizing the tank from a pipe nipple; but that was more of a closed system. Come to think of it, it didn't make of a difference to tuning.

I probably won't do much else. I installed an exhaust diffuser on the stinger of the pipe. I'll see how that works tomorrow.