307 heads on a 355??
i agree with zones89rs find yourself some vortec heads because they will flow worlds better than those 307 heads
the vortecs are getting pretty cheap these days as well i found a set with only 18,000 miles on them for under 400 bucks they will just needed a little machine work for higher lift and larger springs
they will help the motor on the low end, but choke it on the high end.
also, know that if ur not the original owner, no telling what heads u have on the 307


