I am buying a 2002 Gen6 500hp and wanted to know the (easiest) best way to get 500 to 550hp. Also what is it stock. Thanks in advance.

heads and a cam. it's EFI so resurch who has done this and go with an experienced builder. I have tried the external add on crap for the EFi and nothing reall works.

Or do what I did over the winter and Whipple it !

Is is EFI or carb..could be either one....if carb..you might consider a 250 blower setup, run about 4psi or so..you could also do some porting on the heads like Jeff suggested and prob gain nearly 50hp..not sure if I would touch the cam or not..those HP500's have great cams in them that work very good and no rev problems, but that is also a choice...btw..stock hp is 500 @ the crank and 470hp @ the prop

After thinking about it..I guess you could only have a efi...carb was made until 2000 and efi started in 1999...so maybe the head work would be a good choice...OR THE WHIPPLE!

Stock power for a HP500 is 470 hp.
Tyler Crockett redid rebuilt both of mine recently.. basically heads, cam, ignition.. dynoed out at 585 hp at 5600 rpm.

Bajapred is right, stock power is 500hp, not 470.

I didn't think Merc still built the carb version in 2002.

The quickest and easiest path to 550HP.... well take off the EFI system and intake and sit it on the shelf....then bolt on a single plane and 850 and spin the motor 5800....and yes, I am being serious....If you're going to SC, no need to stop at 550....go whipple or roots with carbs and put up 800+ reliably....

I didn't want to lose my efi, if he's anything like me, he won't either. What about just swaping out to Aluminum heads? That should be good for 40 hp.....no?

Carder,

What speeds are you seeing? What is your set-up?

I am told it is a 2002 but it has a carb, This motor is going in an Advantage Citation 22ft. It has gil exhaust right now.

Don't waste money on the exhaust, you won't get any more hp. Those Gil's flow great.

If it's a carb, you have alot of options open to you.

If I were you I would fine a good engine guy close to you, check him out (talk to his customers) and then ask him what he would recomend.