Best Mopar engine of all time
426 Hemi is the top of them all, still being raced after almost 50 years.
you can buy new blocks right here and build your own:
http://www.keithblack.com/racing.html
they can be stroked all the way to 605 c.i. and can be dual turboed, supercharged, injected, whatever. best of all they will handle the power. that is their main benefit.