right now iv got a 306 in my car thats in need of a rebuild....is it worth it to go with a 347 stroker or just leave the motor as a 306?.......is it much of a difference in power from a 347 vs a 306?........my mods currently are 306, holley 65-dp carb, torker intake, ported 351w heads, crane roller rockers,x-cam,pulleys, long tubre headers, n.o.s 200 shot nitrous kit, scat crank