Jet Boat

[cruizer]

OK, have a little 454 high perf engine, pushing around 440 hp on my 19' Cougar shallow V jet boat. Think about modifing it for a little more jam. Say if I wanted another say 100 hp, what could I do other than Nitrous (which is still an option). I've already ordered a set of twisty Bassett headers for it.

Timed at 35 deg
roller rockers
marine cam
Edelbrock torker II
Edelbrock 800 cfm carb
MSD HEI
Holley electric pump & reg
Berkeley pump, high volume loader and stainless "A2" impeller.
Hydraulic place diverter system (for the 300' rooster tails)

[Mr Bigs]

The only way you're gonna get that kinda bump is forced induction turbo or supercharger. If so I hope your internals are up to it and fuel injection is a must to tune properly.

[FusionKing]

Get the headers for sure. What are the heads exactly? Later version heads are sometime way better whether factory HP or aftermarket. That Intake really is not all that great for sure. Nitrous is certainly a bunch of fun and could save you a bunch of money overall so you could have a better cruising set-up between blasts.
Depending on your compression ratio you might play with supercharging it as well and gain a good bit more than a 100 ponies.

[Crookedrecords]

There are a million things you can do to increase the performance of the boat without having to mess with the engine including but not limited to changing the pitch on the impeller. An A cut is gonna load up up really quick on ya. Your hole shot is gonna be good but your top speed is gonna suffer. What is your top speed and at what rmp? 440 seems like plenty of ponies I don't have nearly that much and was doing over 70 mph with a C cut but hole shot sucked as well as gas mileage. Remember if ya get to wild you may have to step up to race gas which is a real pain as well as expensive. When i went to an a/b cut my top speed dropped a bit but my launch was awesome and i could run all weekend on one tank of gas, one thing to consider if the prices jump up again. The best thing I can do is point you to the best in the business. Check out the jet boat sections of hotboat.com and www.performanceboats.com they are VERY helpful and there is a TON of info. Many are professional racers and are willing to share their knowledge.
Notice the name of This boat.....

[SundownIII]

Cruiser,

Won't get into the specifics cause I've been away from that (Hi-Perf) side of boating for a number of years.

A few things haven't changed though:

More Fuel + More Air = More output (HP)

First thing I'd be looking at would be the fuel/air delivery.

[Laiky]

I would suggest a set of aftermarket heads (you didn't mention what your running now but 440hp on a 454 implies factory heads). AFR for instance, makes some of the best flowing heads on the market. On a small block with a healthy cam, it's not unrealistic to pick up 70 hp depending on how crappy your heads were. Either way if you intend to exploit those cubic inches heads will be your limiting factor. Any other mods you make will be less effective with poor flowing heads. In my opinion, it's the limiting factor for power.

[SundownIII]

Crookedrecords,

Sitting here LOL.

People on here think welding can be an "expensive hobby". They should try performance boating.

We've got a 38' Fountain with triples in for engine replacement (all three). Using just the Mercruiser Hi-Performance engines (nothing really exotic), the owner is looking at a 100K+ tab when all is said and done.

A man could outfit a heck of a welding shop for that kind of money.

[cruizer]

Don't think I'll go blower or turbo just yet. When I get a low compression race engine setup for a blower.

I like those zoomie headers, just thought them to be a too little loud on the rivers.

I'll pick up a set of aluminum heads, and a cyclone intake for this year of running, and a new crate engine for 2010

[bretsk2500]

The only way you're gonna get that kinda bump is forced induction turbo or supercharger. If so I hope your internals are up to it and fuel injection is a must to tune properly.

any purpose built marine engine is going to be all forged internals... High performance marine is the most severe duty cycle a IC engine can see short of top fuel...

[bretsk2500]

We've got a 38' Fountain with triples in for engine replacement (all three). Using just the Mercruiser Hi-Performance engines (nothing really exotic), the owner is looking at a 100K+ tab when all is said and done.

A man could outfit a heck of a welding shop for that kind of money.

about 3 years ago I was accessing building damage due to a asphalt tank explosion at a local factory (they make "Ice & Water Shield" type products). The owner lets me in and we walk by a vintage styled 30'ish all mahogany off shore boat with twin Allisons on it... It was the most beautiful boat I've ever seen. My jaw must have been on the floor because the owner just grinned, even though there was a 40'X50' hole in their roof...

I can't even imagine how much that boat would cost to fuel... let alone own.