Lightened flywheel and crank pulley

[Niall]

i couldn't get out of him the difference in the two
other than

There's no way to tell them apart really - the ring gear are the same size, although the offset is different

i found out
early ones EN8D grade steel have smaller ring gear
later EN19T chromoly steel have a larger ringear

i was trying to work out if the one i bought was an early or later
anyone else shed andy light on the differances

i believe the timming mark teeth are cut square on one and have a triangle airspace profile on the other but i bont know on the version for each

Easiest way to tell is the noise it makes when you start it. If it just sounds like a stock engine when cranking, its a later one. If it sounds completely different, its a early one although did you not buy yours new when you first got the 6? If so, it will be later as IIRC the first gen ones were stopped bloody years ago.