Confused by piston rings...

[prothed]

Just fitting some rings (Sealed Power E-424K) and the instruction sheet doesn't match what's in the box...

The label on the box says the rectangular section ring is the top ring, and the ring with a bevel on the top inside edge is the second ring.


No problem - but the instruction leaflet shows both of these as top rings, with the second ring having a bevel on the bottom side


Don't want to screw this up - which is which?
Thanks.

[femtnmax]

The leaflet is correct, just that if you have a ring with bevel as you have, then the bevel on the inside circumference is the top ring.  The bevel gives extra surface area for the combustion "pressure" to push against, this helps force the ring against the cylinder wall.
The "square" shaped ring actually has a twist to it, so with the dot facing up the lower edge of the ring will contact the cylinder first.  This helps this "second" ring scrape oil off the cylinder wall as the piston travels down the bore; removing oil is its real purpose. This ring does not add much if any to combustion sealing.
Keep in mind the "dots" always point "up" toward cylinder head surface.
Would also be a good idea to fit each top and second ring to its cylinder and check for correct ring end gap.  Grab
ends of ring and "reduce" its diameter to slip it into the cylinder, then push ring down cylinder about 1-2 inches, and be careful to have ring not twisted or cocked in cylinder, maybe use upside down piston to push ring into cylinder.  Then measure end gap with feeler gauge.    Typical street performance gaps for top ring are 0.005 inch per inch cylinder diameter, that means 4 inch cylinder bore will need top ring gap of 0.020 inch.  Second ring should be equal to top ring, or slightly greater.  Setting second ring this way helps prevent ring flutter at high rpm.   They used to say gap second ring LESS than top ring, but current research is suggesting otherwise.  Ring gap increases for race use, or heavy hauling truck type use due to extra heat expanding ring, thus reducing the end gap.
If using KB pistons, they require special top ring end gap to account for heating of piston head, so always best to read piston specs to see if special ring gaps are required.
Use ring gap filler tool, or hold ring in one hand, and gently hand file ONE end of ring, so you can keep the side your filing parallel to the ring end that was not altered.

[prothed]

Thanks for this.
I've been given a link to the manufacturers application guide -

http://www.federalmogul.com/korihandbook/en/section_18.htm

but that just says that either type of ring can be used in either position.
Maybe it doesn't matter in practice - maybe I worry too much...