Aftermarket iron wedge block for 540cu in. Custom pistons to match the heads, 4340 crank, good rods, roller cam, I'll bet you have $10-12k in the short block
440-1, B-1, indy 572 to make power with that big a motor, plus pro porting.... $7k up . So maybe $20k or more, if pro built and assembled.
Chevy 632, good parts thru out, dyno'ed at 800+hp (with lots of room to make more) and at your door in a week, $14k.
Mopar is hard.
