misfiring problem help!!!!!!

[mike78nc]

I have looked everywhere and can't seem to find anyone with the same problem. Me and my dad just build a 350. We put new 375 hp angle plug heads on it with an aluminum air gap intake. Also a new cam with 230 duration and .495 lift. It also has an 800 quadrajet on it. The motor is 1970 model 350 4 bolt main. The motor is in a 1985 GMC pickup. The problem we are having is no power. The truck has no power at all. The truck has a splutter out the tail pipes and it also has a few plugs that are soot black when we pull them. This means they are getting no fire right? We originally thought that it was the cam or the heads, but we ran a compression test and all of the cylinders had great compression. Can anyone help me because I am stumped.