It's called SD power pack put out under crusader http://www.michiganmotorz.com/vortec...ine-p-796.html

Well I have to eat my own words here and I have said this before - never assume every question up here is a Mercruiser so with that said about posters not putting all the info and important information asking for help. So if we do not know exactly what you have and all the detailed info posted, how does anyone expect to get quality and correct help. Just saying Like anyone would have known.

Here we go again - I call the Auto parts store - Parts guy - hello - caller - I need a starter - parts guy - whats the application ? caller replys - a chevy - parts guy - good bye - click

Is this is a mefi system you maybe be in luck, that is you can advance the timing to tame the cam down from 600 to 1200 rpm maybe even up to 1500 rpm that is if your cam is reverting, If its a 555 well you have your work cut out for you.

Most likely MEFI 4 - ECM for this app

Pic#7 shows it's a Pleasurecraft Marine engine.
http://www.michiganmotorz.com/vortec...ine-p-796.html

SB - Crusader and PCM are the same company out of South Carolina and for the past year have been owned by Correct Craft Boats. Yes a wakeboard boat company owns these engines companies. Actually that is one way to get you engines into the boat manu's - heck why not own the engines companies to and lets throw them in the boats we make is their moto.

http://www.nautique.com/press/index/...usader-engines

Would it be worth going to dry exhaust. If so what's entailed.

Dry exhaust takes the fun out of boating...unless your boaing is just occassional high speed runs. IMHO.

So, you did not answer - what computer do you have ?

I can deal with the noise I can't deal with the reversion. Sorry it's the 555