I've tried everything to fix the miss. there's no miss when it starts up, idles, or when you punch throttle. the miss is there at ordinary cruising speed which baffles me. i've changed carbs/msd box/distributor/wires/plugs/fuel pump/coil with no luck. offically stumped. a tech at msd & holley said to take a look at the timing chain & the cam to see if something wrong with the chain. welcome to this nightmare....