hi guys again,need your help again.........what piston best suited to my merc 700x and 650xs 3 hole banger as you say plus what best pistons to put in our omc stinger,stinger is standard and mercs have had very seriuos modding very short halves and carbs bodies,lightened,skirted pistons and lots of flow mods internals..pistons in use at mo are 3 ring and two ring with no other markings,some have ribs to skirts poss to hold oil?????? are these wiseco????i,m nearly there with these antiques just abit more info thanks for all help so far......these motors are to go on monos and cats ..t850 and f3/4 cats......jon