Gen one and gen two piston/ring questions

[Ernest Montague]

Anybody know the difference in the two different pistons and rings? I 
measure the newer and older rings against each other and they seem the 
same

Actually I measured against the 1140 20F00 000 ring set



7-1
PISTON
12111-20F00-0F0
2
$64.40
$61.18



7-2
PISTON
12111-20F10-0F0
2
$74.97
$71.22



8-1
RING SET, PISTON
12140-17G00
2
$29.08
$27.63



8-2
RING SET,PISTON
12140-17G20
2
$44.96
$42.71