airjunky

iTrader: (2)

And if you did have the money a lingenfelter lt1 or DART ALUMINUM based 406 will make silly silly power .with less engineering .being in a boat with a wakeboard tower that will do almost 80 and holeshot like a floating gmc syclone will distort your thinking

tomtbone1993

iTrader: (3)

the wakeboard boats have been using them for years....

mike tkach

iTrader: (3)

i would not be suprised to see LS power coming from mercury marine in the near future.

SkiDoc

iTrader: (4)

You can buy a Pleasurecraft Marine 406 HP 6L Lt1 with closed cooing and exhaust for 12K. They are pretty much bulletproof. It is a good bargain and Pleasurecraft does a great job with all their marinizing. Water pump impellers are a breeze to change. They also have something called a fuel control cell that prevents vaporlock. I think they maybe ahead of mercury. I have had these engines in my skiboats and I never have issues. Look on Discount Inboard Marines website for them.

mbobb

I did some research a year or so ago on this and a similar cheap option would be to go with a truck 5.3 engine and build from there (these are readily available on ebay and salvage yards). I don't remember everything I had researched but I recall they have 6 bolt mains and were bullet proof, MSD or somebody makes a controller that allows you to swap over to carb and keep the tuning simple. I found a few dyno results where guys were just putting a decent cam and heads on it and were making some very respectable horsepower and the things rev like crazy. I think it would be a cool cheap swap for the right person.

mbobb

Also Lightning makes LS headers that aren't insanely priced like some of the previous options were so other than converting to closed cooling if it's in salt water I don't see any big issues in the swap.

http://www.lightningheaders.com/5403...erc_header.htm

myturn

Thanks Guys,

I got a lot of good information from this thread.
I seems to me the key problems are:

1. Exhaust manifolds. You may have to run a dry stack
to avoid reversion.
2. Does the Direct Injection pose any new problems.
I would think it would be better since the air/fuel
is not mixed in the manifold.
3. Maybe you need some protection for the electronic controller.
Probably not since GM electronics it pretty reliable.

I would think you would save 500lbs/engine. This would more
than make up any lack of torque which I don't think is lacking
in the new LT1. When it is time to refresh/replace my 496 HOs
this is certainly going to be an option I will consider.

Thanks,

Warren

BUP

iTrader: (9)

And Volvo Penta has been using them for the past 3 years and has came out with the new 4.3 LS marine version 240 hp that the GM trucks use currently. Its direct fuel injected and runs like a 350 HO MAG. That motor really accelerates hard especially for a V-6 as I test drove one in a new 2015 - 21 ft Regal BR.

Mercruiser's plan is not to use any engines and or parts directly from GM. They have a foundry making some of their engine block models currently. Mercruiser tested GM LS based engines back in 2009 for their marine use and even made announcements to its dealers that the new GM LS engines were coming in their line up but dropped the plans later in the year. IMO Mercruiser is or wants their engine blocks made & build everything in house down the road.

BUP

iTrader: (9)

Also Motor Trend new 2015 Vette that they had as a testing model to report on for the magazine - the engine failed at 6000 miles and has raised concerns at GM. The word out about the engine failure is possible material from the internals of the oil filter let go and caused the engine failure. No word I heard as of yet for new info about it nor to 100 % confirm if the material form the oil filter caused it..

sea6

They also make computer sit-ups to put LS in an old chevrolet or camaro. I was thinking the computer would be your friend as they can be tuned from a laptop.