Im not repowering my triple sonic...
This is only a fun to discuss question!
Lets say you start from scratch, forget about the drive you have or height available under the hatch...

You wake up one day and you need 650-700 hp, wich route are you taking, and why?

Simple as that!

BIG, because you cant beat CI,, and that saying has been around for years.

Blown 540. Reason being is set the bottom end up right. Keep compression low and it becomes easier to add boost for speed later if you really wanted. Build it N/A and your compression will likely be higher so you have to be more careful adding boost when it isn't fast enough and let's be honest. It's never fast enough. Lol

You can beat CI, with forced induction. You can also beat CI, with a properly spec'd smaller engine, vs an improperly spec'd larger engine.

Nice thing about a blower , is that it allows for a mild valvetrain. The big block chevy valvetrains are their weak link. By utlizing forced induction to meet your power goals, it can allow for a milder valvetrain, and an overall longer lasting engine.

Mercury has every bit of information, parts, resources, and financial backing, to build 700-800-1000hp engines "on motor''. Theres a reason they use superchargers in those applications.

It all comes down to what you want, how much you want to spend, and so on. If starting from scratch, a 700HP compression friendly 572-598 is a nice package , and then when the time comes you want more power, (everybody does at some point), installing superchargers on them will get you there.

efi'd whipples on 502's will be hard to beat.hp500efi cam and old junkie 088 iron chevy heads.you can pick any exhaust.700hp at 5lbs boost.

I'd start with a 632 Dart M block and have a mild big horse power that would last. Instead of forcing air down its throat!

I'll throw this in, Wagner Diesel.

And the stock GM bottom ends will live fine at that power level. No need for new cranks, rods, pistons, oil pans, cylinder heads, and so on.

Full force tim has probably wasted 40-50 thousand on replacing his 420hp mercs in his old cig, to make his boat go 10mph faster by going to bigger cubic inch engines. 3 years ago, he could have done a basic rebuild on his old 420s, a cam upgrade , slapped a 250 blower on them, and made his 630hp he just made with his new engines, with alot of gas money leftover.

I found that it would be cheaper to supercharge than put a good top end and valve train on a motor.

I used to be hesitant on blower motors due to ignorance. Now I want one. They can be set up mild. Make great power and be reliable. Make great power to boot.