the standard 305 valves in '76-'79 were 1.72"/1.50", thereafter they all had 1.84"/1.50". and even if you have a regular version, a set of vortec heads and a COMP XE268H10, with an RPMAirGap and a set of long-tubes will get you 370 HP at 6100 rpm. Trick Flow makes a set of heads just for 305s. |