I guess I had missed the post "SLAMMING" you. I feel that we all have info to share, and promise you my support. If you haven't guessed by now, my emphasis has been on "Stuffing" the crankcase. That is why I have mentioned the different back plates and reed valve arraingments. I cannot determine to date if smooth back plates, or partially inclosed reed valves are best. I do know that the early crankcase gives me best performance to date. I am adding additional material to the backplates from the "STIHL" labeled units because are smooth and easy to add material. I am fighting a severe infection at present, so my testing is on hold, but it don't stop my thinking process. I am at 3650 ft elevation, which makes a difference also. Keep up the good work, and keep us informed. FLATHEAD 4