I went with the Worlds product Man Of War block
http://www.worldcastings.com/.
2 reason, 1st they are right on long island In S/C. 2nd Block is said to hold up to 2000 hp.
Here are some pics of the block
TECHNICAL SPECS
Material: High density cast iron
Deck Height: 8.200"
Deck Thickness: .600" minimum
Cam Bearings: Stock - can be bored to 60mm
Lifter Bores: Cross-feeds between pairs to maintain pressure
Bore: 3.990" (bore to 4.000") or 4.115" (bore to 4.125")
Cylinder Head Attachment: Stock plus 2 extra head bolts per cyl. (not req.)
Maximum Bore: 4.200"
Water Jackets: Expanded for better cooling
Lubrication: Priority main oiling system
Filtration: Integral mount for spin-on filter
Oil Pan Rails: Stock Ford
Crank Clearance: Can use up to 3.500" crank
Main Caps: Splayed billet steel, nodular iron, 4 bolt
Oil System: Has .500" feed; bosses for dry sump
Weight: Approximately 200 lbs.
TECHNICAL SPECS
Material: 357 T6 Aluminum
Deck Heights: 8.200"
Deck Thickness: .600" minimum
Cam Bearings: Stock - can be bored to 60mm
Bore: 3.990" (bore to 4.000") or 4.115" (bore to 4.125")
Cylinder Head Attachment: Stock plus 2 extra head bolts per cyl. (not req.)
Maximum Bore: 4.155"
Water Jackets: Expanded for better cooling
Lubrication: Priority main oiling system. Dry sump capable
Filtration: Integral mount for spin-on filter
Oil Pan Rails: Stock Ford
Crank Clearance: Up to 3.47" stroke
Main Caps: Splayed billet steel, 4 bolt
Oil System: .500" galleys
Weight: 108 lbs. with caps and sleeves