as others have said, longest rod possible to keep piston velocity down...the best tq/CID ratio I've seen is 1.4-1.5 lb-ft per CID, so at 400 cubes, you're looking at 560-600 lb-ft max. which means you'll be ~9-10k RPM to hit 1000HP with peak torque happening up there.

sounds like basically you'd need to take a winston cup motor, scale it up 15% to 400 cubes, and then a little more....they're making ~850HP from 355 cubes, IIRC....

probably B1 PSO heads would be your best bet for a big block, maxed out W9 raised port for a small block? wonder how much you could coax from a 6.4L genIII hemi, if you could come up with a valvetrain stable to 10k RPM?

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1986 Silver/Twilight Blue Chrysler 5th Ave HotRod **SOLD!***
2011 Toxic Orange Dodge Charger R/T
2017 Grand Cherokee Overland
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