estimate horsepower, improvement advice

I am wondering if you guys can help me determine an estimate of how much horsepower an engine I am putting together might make. Also any suggestions of how to improve would be greatly appreciated.
The block is a 4 bolt main, cylinders are bored +060, sorry I don't have the casting number can get it tonight. Crank is a forged (wide seem) with 454 stock stroke. Pistons are Arias, only numbers on these are 4224, they have a large dome shaped for closed chamber heads. rods have a dimple near the top, I think that is pretty good?
Heads are casting number 3873858 and appear to polished and maybe slightly ported (don't know by who so this could be good or bad). Isky z-90 cam, unknown valve train components so likely will replace springs and pushrods etc. Has roller rockers with no ID marks on them. They are silver, aluminums.
Intake is GM- 6269318.
Still need oil pump and carb (have a large stock depth oil but wider oil pan).

Motor will be used in a lake racer class jet boat

Thanks for any assistance

not so much what parts you have but what you do with them as for prep it is not so much Ato B there alot of small things that builders do that make them live and get more power out of them . as a builder i do not care much about a casting number one from block to another long as parts will bolt up or can. what i meen is if your mixing mark 4.5.6 parts .size of bore piston to wall .deck plated .pin fit. end gap . mains and rods size . re work the piston domes . stuff like that then cam number help and whats been done to heads what size valves .what is the cc of the chamber s whats a very old head about 109 cc 375 hp head . whats the cc of the piston dome . so not to be to hard on you have not told me much steel cranks and four bolt mains do not make them run any faster and you pick out the cam so ? its a done deal