before you spend money to cut the heads for compression you should read this:

http://www3.sympatico.ca/big-d/460.htm

this guy made a 460 inch motor by grinding down a CAST crank to 400 mains and ofset grinding the rod journals.motor was built for 1500 bones and ran tens for years in a 3400 lb mirada.do the math

400 stroke =3.38
440 stroke =3.75
pistons move up .37 with a (free?)cast crank,how far are your pistons down?how much quench right now to the flat side of the chamber?