Since I’m at work and can only study I think I have come up with some generalizations about bv’s. 1. They are more tune able by vent and bv chamber size than hammer strike. 2. They work within a smaller tune window than hammer tuning but have the advantage of opening large valves with less hammer force. 3. Maximum poppet lift is dictated by travel within the balance chamber then hammer bounce/crash occurs. 4. A bv can ‘blow open’ and ‘hold’ open, but offers nothing to closing force5. The tuning of the ‘hold’ open is what gives us dwell With these things in mind, could we limit the travel within the chamber to just the cracking distance, run a large vent to speed the neutralizing of the bv, extend the poppet stem back out to allow hammer movement (dwell) and ‘float’ the balance chamber not only a touch radially (for machining tolerance) but also allow it to travel with the poppet away from valve seat. If the bv gets negated as soon as valve cracks, then we might possibly have a larger tuning window without altering the valve itself. I scribbled it down. Just a thought. Dave