You are defiantly going to need to bore and stroke to get 700 out of it. Well, I should say if you want a steerable 700... And then again, we all have a different opinion of steerable....

My build is a siamese block, 4.5X4.25, 540ci. Around 10.25:1, Stage V heads prepped by FHO, and the cam is roughly 248 @ .050 .605 I .580 E. Numbers probably aren't exact, but close enough. MSD with a Chrysler electronic distributor, Stage V intake with 2 Edelbrock 650's.

Dyno'd at 712 HP @ 6000. That was at 34 degrees timing. It was pulling 6-7 more hp per hundred RPM at 32 degrees, but that was the end of a long, long day, and it was good enough for me!

I chose a somewhat mild cam, for 540 inches, as I wanted power, but streetabliity. There are times when this car gets driven a lot.

Two things to keep in mind when buying and building your motor, how much power will your car handle and how much power can you handle?
On that block, does the oil pump pick up screw into the block or is the block machine for the bolt on adapter like the Worlds blocks are? If bolt on try the 4.375 stroke with BB Chevy 2.200 rod journal sizes, if not use the 4.25 stroke with the BB Chevy H beam steel rods
As far as the heads, intake, carb. sizes and camshaft buy bigger than needed for stock C.I. size motor
I'm building a 572 C.I. pump gas hemiroid motor now for a local customer, it will be EFI with dual 4150 bolt pattern 1000 CFM dry throttle bodies with FHO prepare Stage V aluminum heads, FHO Stage V rocker arm assembly, EFI intake for the dual throttle bodies, solid roller cam and so on. I'm hoping and expecting 750 + HP and similar torque
I cam and do make more HP with wedge motors similarly equip than I can with 426 style Hemiroid motors

call Tim at FHO he'll tell you Exactly what you'll need even if he doesn't build it. (let him build it!)

Did Tim at FHO build your Hemi? Roller Cam? What Rockers?

a 4.25 crank with a 2.2 rod journals is about perfect for your application. It will fit with the internal oil pickup. A 4.375 might fit, depending on the block, so had the hole a little farther out. 700-800 horse should be easy with the right cam and heads, and decent compression.

Mickm, I'm sure there is a reason you went with a small cam like that, but I think you are leaving 100 horsepower on the table.

Yes, I defiantly am. As I mentioned in the last post, long conversations with Tim. In the end we went with that cam because:

1) I didn't want to be messing with new lifters all the time. So I have good lifters and a relatively mild cam with mild ramps.
2) I wanted it to be drivable, my version of drivable. Car gets driven a lot at times, about to take it down to LA, ~400 miles. With the 2X4's I would get ~14mpg on the highway. Not bad. Will be interesting to see what it does with the six pack.
3) I can only fit 275/60 tires under there. As it is these are useless in 1st and 2nd. I didn't plan on anymore frame modifications, so knew I wouldn't even be able to hook this power well, so with the above 2 factors, this was good enough for me!