930 Pistons, How do they fit????

[tab tanner]

I'm working on a 77 930 motor and I need to know which way the pistons fit, they are flat tops so there are no valve pockets. The wrist pin is offset to one side.

I can't find any markings on them that say top or oben I have looked.

PLEASE HELP ME if you can! You can call 419-957-7210 or e-mail me Thanks TAB

[garibaldi]

there shoudl be a stamping on the dome of a little picture of what resembles a crankshaft, that faces the rear. If you cant see that, flip the piston over, and look at the pin boss to the right and left of the wrist pin, measure each to find out which side is thinner. . It may not look it, but the pin boss is offset to one side by about .100. The way you want to have them installed is if you were looking at the motor, head on from the front or crank pulley side, not the flywheel side, the wrist pin offset shoudl favor the back of the piston, or the thinner side of the boss faces to the right, or down in the case of a 911( on the 1-3 side, and up on the 4-6 side). The idea with the offset is to have the piston rock over TDC befor the wrist pin does with the rod, to help keep it quiet. SO if I have confused the hell out of you, think of it that way, which way do you have to position the offset so that the piston gets there first, not trails behind. Draw a picture if it helps any. Good luck. I bet if you cleaned the domes, you will find the markings though.

[tab tanner]

Thanks I'll look