Asking for opinions here

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Rich Andrews
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Asking for opinions here

Post by Rich Andrews »

larger deckover hull not heavy but not necessarily too light...

LS motor...Fuel injected or Carbureted?

Gearbox, and I know this sort of depends on a lot of factors but let's assume it has a nice flat torque curve 2500 RPM's on up.. 3 blade prop, would you go with the 2.68 or a 2.38? 2.55?

And for prop that has become really complicated, what's the best pusher prop now?

I like to ride slow and dont care a thing about going fast, but do like to plow thru stuff.
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Andy
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Re: Asking for opinions here

Post by Andy »

JMO. 2.68 & a R

hdsadey
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Re: Asking for opinions here

Post by hdsadey »

Fuel injection definitely.
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Rich Andrews
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Re: Asking for opinions here

Post by Rich Andrews »

What would Tony say....
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One Eyed Gator
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Re: Asking for opinions here

Post by One Eyed Gator »

I have put together 4 ls boat only 1 is EFI other 3 are carbed. All run great with somewhere around 400hp. They are all heavy gulf fishing rigs.
2 are 2.68 2 are 2.55 all have 80" 3 blade setup. both the 2.55 run Maximus blades not fast but push like a dozer. the 2.68 are both R blades great across the rpm range. Carbed boat run good but where dialed in with a wideband o2.

Still learn the EFI stuff myself but I like it. I want to know how to tune it before I personally run EFI.

My 2 cents would be EFI, 2.55 ratio with 3 blade 80 or 82" prop or maybe a shorter 4 on a deckover depend on HP.
I would like to try the newer wide J series prop sensenich but hard to beat an R blade.

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John Fenner
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Re: Asking for opinions here

Post by John Fenner »

I'd suggest a 7'6" x 13'6" .090" deckover with .050" decks, a 2.68:1 gear with a solid built LS, waterthunder is the choice of best built in my opinion, and a whirlwind whisper tip 4 blade or better yet stump puller 80" air screw.
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Re: Asking for opinions here

Post by CarMotorBarge »

How many RPMs do you plan to run at WOT? This answer will help determine the gear ratio. Also a 4 blade is a better pusher prop than a 3 blade if you have the HSP to turn it.
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SWAMPHUNTER45
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Re: Asking for opinions here

Post by SWAMPHUNTER45 »

The new JX series will give you what your looking for to push a load. If your staying under 15ft get a nice LS from Dave or Mike.

If your going heavy 15 or bigger then a BBC would be my advice.

Generic recomendation on drive ratios
2.68 for the LS
2.55 for a BBC

Rich Andrews
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Re: Asking for opinions here

Post by Rich Andrews »

anyone running an LSA?
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Seven3
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Re: Asking for opinions here

Post by Seven3 »

Man, I’m glad I sold my Thurman to someone else, I would’ve hated to see you remove the 540 and put an LS on it lol. Just kidding, who’s building your hull?

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Re: Asking for opinions here

Post by SWAMPHUNTER45 »

Reach out to the DiggingFool he has a fair amount of LSA experience.

sarros2004
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Re: Asking for opinions here

Post by sarros2004 »

Totally new to airboats, but have been working on cars and engines most of my life. My opinion is fuel injection all the way. You invest more up front in both money, and setup time, but once they are tuned correctly you have little issues. True tuning is an art, part of the initial investment should be a well known tuner who has knowledge and experience. I would also reccomend one of the "factory" type setups, as opposed to the versions created by Holley or someone else. The benefit being a factory ecm can be programmed using software like Hp tuners or EFI live. You have more control of the parameters like timing advance and fuel trim. Companies like PSI can help you get set up with a harness and ecm if you do not have one. My advice with injection though is find your person who will be tuning, and let them guide you on which equipment you should run.

Rich Andrews
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Re: Asking for opinions here

Post by Rich Andrews »

Seven3 wrote:Man, I’m glad I sold my Thurman to someone else, I would’ve hated to see you remove the 540 and put an LS on it lol. Just kidding, who’s building your hull?
That boat would never get a CM out of respect for who owned it.... ill surprise you sooner than later on this one!
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Rich Andrews
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Re: Asking for opinions here

Post by Rich Andrews »

So the LSA's are totally bad ass when set up properly, just a bit pricey for me now but if I had the extra ching it would be an LSA motor. Lots to read and learn on these LS motors, and lots of opinions on what to do here. I'll prob just go w a fuel injected 5.7 and your standard 2.68 box and hopefully decide on the right prop for it.

Appreciate the replies. I only wish Tony would sell me his cam grind :)
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digginfool
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Re: Asking for opinions here

Post by digginfool »

Rich Andrews wrote:So the LSA's are totally bad ass when set up properly, just a bit pricey for me now but if I had the extra ching it would be an LSA motor. Lots to read and learn on these LS motors, and lots of opinions on what to do here. I'll prob just go w a fuel injected 5.7 and your standard 2.68 box and hopefully decide on the right prop for it.

Appreciate the replies. I only wish Tony would sell me his cam grind :)
The LSA was a long and demanding journey for me but once I got it dialed in, I'm quite happy with it now. If I had it to do over, though, I would not have gone this route. That being said, my buddy just built a boat with a FI 5.3 turning an 80" 3 blade through a 2.68 box. It runs really good. His boat is a 14 ft Panther open hull with stainless rigging but just the same, it was a nice, inexpensive build for him. The only mod he did was I gave him the stock LSA cam out of my engine and he used the Holley fuel injection (not the Dominator though). He had an article with the exact same setup and the engine made 385 HP at 6,200 RPM. I'm pretty sure he's close to that the way the boat runs. Good luck on your build!
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One Eyed Gator
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Re: Asking for opinions here

Post by One Eyed Gator »

Rich, Check out
LS1tech.com
Pirate4x4 the tech garage section
I hate to says this but facebook Richard Holdener has done a bunch of testing with different combo's site
Hot Rod has has tested 20 intakes and for what we do RPM wise the TBSS inake while ugly works very well up to about 5500rpm


If your going to build it yourself look at scroggins-dickey they were just selling LS9 block for 1700.00. They for time to time have great deals. LS2 block is 1264.00 or is was.

Yes all kinds of options
6.0 LQ4 I just built again only around 400-425hp I have about 3000.00 in it. I didn't deep pockets so it took a little while to build.
6.0 with older 706 head (100.00) bumped the stock compression to about 10.4:1 added 2.00" valve. The small runner helps keep the air velocity up. I changed cam, spring, trunnion kit, thicker pushrods, good timing set stock 8qt oil pan.

It is on a heavier 14' Alumnitec for fishing the gulf. Runs fairly well loaded for fishing.

To give you and Idea I had a stock 5.3 same 2.68 box and with 79.5" 3 bld R. Motor turned 5000 set at a little over mark 2> Smuggler help me build a hybrid cage so I was able to swap motors without taking the box and prop off. With 6.0 above it turned 5550 at the same prop setting and was a much different boat.



I copied and pasted the info below.
There are two types of EFI system classified by the amount of the intake air detection method.
GM 1. L-EFI (Air-flow control type)
This type uses an air flow meter to detect the amount of the air flowing in the intake manifold. There are two types of detection
methodsOne directly measures the intake air mass, and one makes corrections based on the air volume.
Holley 2. D-EFI (Manifold pressure controlctype)
This type measures the pressure in the intake manifold to detect the amount of the intake air using the intake air density.

Hope some on this helps

Rich Andrews
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Re: Asking for opinions here

Post by Rich Andrews »

right on... thanks
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Seven3
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Re: Asking for opinions here

Post by Seven3 »

Don’t make us wait...who’s building the hull lol.

Rich Andrews
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Re: Asking for opinions here

Post by Rich Andrews »

Seven3 wrote:Don’t make us wait...who’s building the hull lol.
Who built the hull is the question... remember this is a budget build under 25k with all good quality stuff. just want to bring back some honesty to these 99k airboats.
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pipedog
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Re: Asking for opinions here

Post by pipedog »

Rich Andrews wrote:
Seven3 wrote:Don’t make us wait...who’s building the hull lol.
Who built the hull is the question... remember this is a budget build under 25k with all good quality stuff. just want to bring back some honesty to these 99k airboats.
It can be done! I built mine in that price range, love the fuel injected N/A LS :salute: :salute:
Palm Beach open hull 13'9" with 6.0 F.I. LS - Ox Box and a 3bld "R"

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digginfool
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Re: Asking for opinions here

Post by digginfool »

Here's a link to the article my buddy had. I was a bit off on the specs. The 5.3 with the LSA cam made 389 HP at 5,600 RPM, not 385 at 6,200. Pretty interesting article. Could give you some good ideas to work from.

https://www.google.com/amp/s/www.hotrod ... rison/amp/
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