I thought you might like this little chart from Edlebrock. This looks like the least expensive way. This is without aluminum heads which help make allot more power.
Russ
http://albums.photopoint.com/j/View?u=1595962&a=12199293&p=46423891&Sequence=0&res=high.JPG
Russ
http://albums.photopoint.com/j/View?u=1595962&a=12199293&p=46423891&Sequence=0&res=high.JPG