It is a very expensive way to gain 38ci so about 38hp. Other ways to do it for less money, less hassle.

You forgot less dependable . 38 CI and 150 hp gain is what i'm lookin at and will sell off all the stock HP parts .

for that kind of gain you will need a head change along with the 540 rotator.

I say put a blower on it.

To gain 150HP, you'll need a rotating assembly, even if you go with Scat stuff your looking at 2k, just in crank, rods, pistons, rings with the ARP bolt upgrade.

You'll need to get the machine work done, a new internally balanced harmonic damper and flywheel, probably another 700 or so.

With block machine work, balancing, etc, I'd say you'd have 3500-4000 just in the shortblock.

Youll need a GOOD set of heads. CP sells Dart Pro 1 marine roller spring heads for about 2500 bucks a pair.

A new Cam and say some morel roller lifters, timing chain, possibly pushrods, around 1000 bucks.....

Stock HP 500 carb wont cut it, so figure another 1000 bucks for a new dominator carb.....

Misc gaskets, and parts, another 500.00......

My guess is you'll be somewhere in the 10,000 dollar range to squeeze 700-725HP out of your HP500, N/A.

Or, if the engine is healthy, you can pick up something like this, and bolt some carbs on, and make the power you're seeking for around 3500 bucks....

http://www.offshoreonly.com/classifi...o43863-en.html

Point well taken and will be considered . My HP is in great shape but before i did something like you suggest i would refresh and def go with AFR heads and ARP studs .