steaming pipes

okay my motor is a 318 bored 40 over k.b. 167 pistons zero decked balanced has aero heads that were suppoes to be 318 castings with 202 valves but i think there 360 heads because the ports are big not like 318's they ground the casting #"s off so i can't check i ordered the 318 heads don't think that's what i got i just checked the water again it's full i mean to the top oil looks good no water in it when i crank it up no smoke runs a couple mins. starts steaming alittle then the longer it runs the more it smokes both pipes if you rev it up quits then starts again it idle only not white or blue smoke looks like steam or condensation smoke but it's 70 degrees here today the new cap is holding pressure the seal was blowed on the old one