the 3000 series is, as i recalled, cast. forgings are in the 2000
series.
to wit, all 3.750" bore, 0.931" wristpin:
L3000F 'steel strut' 1.581" ch flattop [199]
L3101F 'braced' 1.581" ch .118" cup 232/258 to '76
L3102F 'steel strut' 1.581" ch .134" dish 232/258 '77-9
L3104F 'steel strut 1.581" ch .140" valve reliefs 304
L3103F 'steel strut' 1.633" ch .158" dish 258 '80-'90
L2340F 'powerforged' 1.598" ch flattop [290]
L2341F 'powerforged' 1.598" ch .108" cup ?
L2360F 'powerforged' 1.598" ch .127" cup ?
L2480F 'powerforged' 1.598" ch .140" cup ?
so the 3103 is an '80s stock replacement cast 258 piston.
and yes, that's what the 3104 description maps out to. maybe they
mean .140" cup with valve reliefs as well? i thought no 304 slugs
were flattops, though the hi-comp 290s were.
and btw the cups above are flat bottomed; dishes are concave.
________________________________________________________________________
Andrew Hay the genius nature
internet rambler is to see what all have seen
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