Bowman rings are the best! they really help overall performance in all respects! Iv got a few engine with his rings in them that idle down to 1000 rpms . will idle there all day , if that answers anyones questions and have picked up 300 to 500 rpm's on the high side .Engines start real easy because fuel delivery is increased there worth every penny they cost which isn't much verses the cost of a airplane! you do the math,
Keep up the good work frank and thanks for the great prouduct !!!