Ring Gap, recent topic, I know, but I cant search. Options

[swood]

KB - 96mm pistons and stock overbored steel barrels. I'm getting ready to ring the pistons and check/set the gap. I believe the gap should be about .006", but can't remember and can't perform a search for some reason (some virus has dissed me).

I placed a ring in the top of the barrel and the gap was around .021". That's a bit over .006". Am I measuring it the right way? I measured my pistons and yes they are 96mm. Of course I 'll second guess myself and check again.

Thanks dudes.

Wow, post #100! I'm getting up there!

[porsche735]

Like I said, I just did this. When you measure your gaps you have to make sure that your rings are inserted square. With .018 you are probably fine, well within spec. I am concerned about your .007" variance (I think the ring is not square when measured). The piston will be sweeping from about 1/2" down to about 3 1/4" down.
What you are referring to is deck height. Figure out what compression ratio you want, cc your heads, and plug the results into the PP spreadsheet.

CR spreadsheet

But, like I said, don't use the bottom part....

To measure the deck height correctly you need to do teh following:
1) Use a few sockets and washers and bolt your cylinder to the case after installing the piston, rings and all.
2) Tap the "face" of the cylinder with a dead blow hammer
3) Tighten the nuts a little bit more. be careful as you don't want to bend the fins.
4) if you have a dial indicator use that to set TDC. Otherwise use the marks on the flywheel.
5) Measuer with a depth gauge at 12, 3, 6, and 9 o'clock positions to the top of teh cylinder from the piston.
6) take the average of the measurements. this is your deck height (if you are not using head gaskets which you shouldn't be.
7) To adjust, you must remove the cylinder, add or subtract shims, and reinstall the piston.
8) oh yea. And after each cylinder is done, have a beer..It will take you a while...

Chris