Hi George,
I definitely agree with Excaliber here. The mass bias positioning is in a pretty weak position for you. I drilled my Machine #2 like this and it's about 5-6 boards weaker compared to Machine #1 (3 3/8x3 3/8mb).
I understand you didn't want anything too strong but the Machine's mass bias is pretty strong, so proper or accurate placement for reaction shape is very important. If you're speed dominant, I'd even go with a lower grit then 2000 to try and get the reaction. Keep us posted and we'll try to help, thanks.
--------------------
Rick Leong - Ten Pins Pro Shop
Track Intl. - Amateur/Pro Shop Staff
Vise Inserts Staff
www.Trackbowling.comwww.startabowlingrevolution.comSee profile for Track Ball videos
*El Presidente of the Track Legion