Other than what I said before I did forget to say..
that the W-2s can be bought in a race or econo version
which is simple to spot.. the race ones dont have the pedestals
for the rocker shafts.. the econo ones have the pedestals..
both sets of mine are the econo versions.. one set is the
short valves the other is the long valve... I have never
had the short valve ones on a engine yet.. I ported them
and there they set.. I didnt get carried away with the
port work on them so they didnt need any tubes added..
I think I have valves for them but I dont know... I might
look to see what I can run for max lift on them just in
case I want to put them on something... they should still
flow right at 300 which is pretty simple on the W-2s