Yes I understand the minus- positive in figuring comp ,was just explaining that minus was referring to 'down in the hole' ......not above deck....thanks for all ur input...my figures for comp r slightly higher than urs maybe the calculator site I'm using differs....still aint sure what I'll do yet but I'm sure I'll get more replies and input along the way....I get the impression that I'm not making any believers in this combo but this same engine in a 70charger 4spd-4.10 geared full weight ran 12.40's with the 562-300 cam but it did...and in the day was in last 2 yrs....same exactblk heads cam/pistons...????????????????????????????????????????????????????