not all 305 heads are crappy, just because it says 305 doesnt automatically mean crap,
theres alot that are 1.94 1.50
if you dont want them then gimme them lol
especially 4416's and such
'80-up ones, any,
perfectly fine to put on a 350
if you feel bad then you can port them out a little with die bit, grind out to intake gasket port opening size, sam with intake manifold
and clean up exhausts too, rmeove bumps, fix corners
youll be fine it will flow fine, unless its some pro street hot built engine lol
the only heads i toss are 624's and 88's
they are crack prone problematic heads, have the 88's magnafluxed before using, and just toss the 624's
otherwise no reason to junk any other sbc heads unless theyre damaged beyond repair/cost