hey guys! i'm not talking about gray hair vs youngblood!just wondering what kind of gains might be realized by going to a pair or world products sr torquer headsw/170cc intake runners,2.02/1.60 valves,76 cc chambers]? .i am presently using 76cc chamber bowtie heads that have 2.02/1.60 valves and some porting.come on! give me your hard earned gray cells! thanks and thanks again,jimm