I'm just wondering what cam would be best for my 330hp mercruiser 454 bbc with twin 60mm M&W rayjay water cooled turbos in an 1988 Chris craft 245 limited I want it to sound absolutely nasty. But minimal overlap so it doesn't suck water back in. All suggestions are appreciated!

Good luck with that! Go dry and go crazy otherwise your limited to the 741 or similar.

Yes. NastEEEEEE
lol. Just makin fun. :wink

The E’s in Nasty is the overlap which csuses the rough idle and the reversion.

I say calm your pants and give the engine whst it wants. It’s a bbc, will have some blurb (looe noise) anyway.

btw: the exhaust wheel on the turbo kinda dampens the noise and pulses.

There's gotta be something that sounds choppy with little overlap atleast a slight bit better with thru hulls right off the turbos even the slightest change should be noticed?

Uhmmmmm I suggest a bit of research on your part... Twin turbos on a 330 and you want it to sound nasty.... Your followup post will be "why does my boat run like chit"

The cam is dictated by compression and heads amongst other things. The 330 has anemic heads. It also has little rods and a cast crank. Not the best for any kind of boost. Its also a motor that in stock trim is done at 4700 rpm. Turbos like rpm, the rest of your motor doesnt.

Not trying to rain on your parade... but for it to work well, the parts need to match. That nasty sound is the side effect of certain parts working together. Your current concept is missing some key parts.

Like Getrdunn said, dry exhaust will sound pretty crazy to most and sound pretty good with a 731 or 741 cam. The problem is that those cams really start coming to life about the time the rest of your motor is done.

From what I seen opening the motor up a bit it does have some serious work done to it I bought it as a complete set up running from another race boat so I'd assume that all performance parts needed to handle the turbos were replaced but I do appreciate the information I'm new to this and will learn.

Well I appreciate the input guy there's not much I can do but I guess re gasket everything freshen the whole thing up top to bottom and do the same to the outdive aswell and just run it the way it came till problems start

No raceboat would have a 330 hp 454. you need to figure out what you have.. What crank? Rods? Block? solid or roller cam? heads ? etc......

I will tear down into it and have some pictures like I said im just getting into this saw the boat and the engine set up kinda fell in love and needed to try to put the puzzle together.