I went from a 305 to a bored out 350.
I was hopeing for a bigger torque difference.
I'm wanting to go big block.

overhaul a big block or rebuild one.

81-85 350. overhaul kit $115 from P.A.W.
80-85 454. overhaul kit $139 from P.A.W.

81-85 350. deluxe master rebuild kit $272/$449 from P.A.W.
80-85 454. deluxe master rebuild kit $468/$567 from P.A.W.