I was wondering which iron block hemi is the best as far as design and stregth? I have a 66' 426 hemi out of a 66 charger which is in perfect shape and has never been damaged in any way. My engine builder wants it for numbers reasons for his car and i have my choice between newer production mopar block or a world products block. I would rather him have the original hemi for numbers reasons and i plan on racing my 69' Roadrunner so i would rather risk damaging a "fake hemi" than damage the real thing. What are your thoughts? Thank you, Bret