The point I'm making is most big blocks of that era 73-75 suffered more power loss then the equvalent small block. a 340 was rated 275 hp a 440 same year was 375 |In 1973 they were 340 net 240 and 280 net 440. That is big diff.I own a 1973 360 low comp is it fast no, but it will run low 14s all day long and it was rated 175 net hp.It will hold 4000 rpm for hours and run on mid reg. This is in a car that weigh's 4260 racing weight.