Here's my two cents worth, I built a 514 ford about a year ago and I used the 429 ,1970 model heads , by the time I paid for the heads and had them rebuilt with stainless valve's ,new springs,retainer's ,guide plates,and screw in studs for the rocker arms , I spent a little over $1100. I think you could buy the aluminum heads for about the same or a little more and get more power and less weight!!!!