I race in T/D and run in the 6.80 range. I am finding myself at the back of the pack and would like to be in the 6.50 range. Combo: 540 BBC, CR 11:1, Big Chief, 871 BDS stage 4 standard blower 46% OD making 20# boost, hats and ports, bird catcher. Question: BDS tech said that all i needed to do was increase CR to 14:1 and reduce OD to 30% and it would haul azz. I was thinking I needed to pickup a used 1471 or maybe send 871 back to BDS and get the air lock rotors or high helix. I have heard someone say that higher CR reduces safety margin. Very often we start on Friday and race on Sunday and I don't like to change main during the weekend as it changes my CA ratio for dial in purposes. What do you guys think?