If it's unrealistic then let's settle for something lower, I'm really just curious as to what can be done with that small of a starting point without spending what the nascar guys are to get their 800hp

UPDATE: Well the motor was just dropped off at the machine shop to be gone through. Guy down there wasn't familiar with boat engines, but does work on dirt track and race cars. Told him to just see what is mechanically wrong with it and I would make a decision on what parts we would go back with i.e. heads, cam, intake etc. Ill post more about what he finds once I know. Both motors are stock 280hp 350's. Im sure someone out there has a recipe for intake, cam, heads, etc.

Woah, time out -- you sure you want a guy not familiar with marine engines doing this? We've all seen it a million times, and is usually ends badly. If it were me I'd go pick up my stuff...

I've got the motor stripped down to a long block, rotating assemblies should be the same?

Here's one I did a few years ago. You could do it cheaper with an rpm air gap or vic Jr. and a decent carb. Stock bottom end, AFR 190 Vortec, GM hot cam, Holley Stealth Ram, HP EFI.[ATTACH=CONFIG]552406[/ATTACH][ATTACH=CONFIG]552407[/ATTACH]

Currently I have an Edelbrock Victor Jr and 650CFM Double Pumper carb on it. Haxby which cam would you suggest? also any beneifts to running electric water and fuel pumps to try and free up parasitic power loss?

Stock 5.7 or 6.2 ?

5.7

Yikes, that's a lot of RPM for a stock bottom.

For a small block Chevy? Not really...