Ls1 upgrade questions
 

Scarab 29 1998 twin smells with work

Has anyone done a ls1 upgrade. One of my companies is small salvage. I don't have a junk yard but we part put mostly small power sports. Anyways was gonna buy two wrecks and get the ls1 motors and electronic and to sell the rest to get the motors for free. Stroke those motors and add blowers. Good idea?? Or bad? Do car motors hold up as well if built right in boats? Any bads and goods to these engines?? I light the fuel injection and weight savings. Just looking for opinions. Big blocks won't fit in mine.

most people will tell you automotive engines have no buisness being in the water...

My thoughts: Your gonna spend a FORTUNE to bring these automotive engines to a standard thats acceptable/reliable in a marine application. I would think it would be more widely accepted to sell your wrecks till you have the coin to do a marine build from the ground up or at least start with a marine rebuild.

Have no issue building marine engines. Just didn't know the differences

they are already being marinized, so exhaust and some other parts are available, these are great powerfull engines for the size, a 6.0/6.2 truck may be the ticket, you will see more of them in the near future...

theres a guy on here that put a pair of those in a 24 skater works great go to skater forums and check it out. ive seen it and heard it and trust me you wont be disappointed.

almost all i o marine engines are car engines adapted for marine use,mostly small&big block chevrolet.

start with 6.0l truck blocks build them with a forged bottom end 4 in stroke (I like callies cranks and rods with diamond pistons) and you have a 408cid, top with ls3 heads and mild cam and you have and easy 500hp,(600hp with a big cam) engine with torque to match. a 6.0l with a small cam is 400hp engine a little more cam and 450hp is easy.The bottom end of ls stuff is miles ahead of older designs 6 bolt bottom ends with cross bolts. the valvetrain is so simple light and reliable. a set of double valve springs, bearing upgrade in the stock rockers and hardened push rods and you are set. I would run holley hp stand alone computer system or mefi4. Hardin marine makes headers and manifolds. Marine power, crusader marine both have manifolds. Look at most "marine motors" and they are slightly modified GM truck engines. GM killed the 496 cause the 6.0l was so damn close in power from way less cubes. (they actually run power management in the computers to keep the drive train alive, and to keep them from making more power, lol) water pump,starter,alternator, and engine management the only things different. any engine builder familiar with marine engines should be able to set up the bottom end. If you are paying someone from start to finish expect it to be expensive, but it sounds more like a diy project and ls stuf just make power way easier than sbc stuff. hell if you know what to buy its cheaper than a bbc up to about 600hp. at that point you have to get a blower or buy a block that can support more cubes,or reliability will suffer cause you will need to turn alot of rpm. so a bbc becomes a better choice. good luck

http://www.offshoreonly.com/forums/s...-bravo-1s.html

This thing is bad ass 103 out of the box! there is and easy extra 100hp in those things with just a and few bolt ons

Those little LS1's will run no problem exactly as they are. If you can get them cheap and they're good runners it would be a great project. Once you have all the marine gear, engine control, and install sorted you can swap them out to bigger LS's down the road if you choose. If you're looking to start from scratch then I agree with the others to choose a 6.0 and build a 408. The Holley HP EFI is a direct plug and play for LS engines so you can keep the sequential efi and factory coil packs.

29 scarab. I don't think you can go any bigger. Is a 6.0 still small block sized? I know big block will not fit in there. I was a fan of the ls1 due to being aluminum truck 6.0 are steel. I just love they way they look too. But your thinking if I get the ls1 and cometely redo it stroke it etc and a blower it's not a good way to go?

Sorry I forgot 29 scarabs have 7.5 beam any will only fit small blocks. 6.0l is same size externally as any gen3 or 4 small block. a blower is great just adds to the cost. how much power do you want is the question? I assume you plan on bravos? (or at least some variation) Gotta keep in mind what kind of power they can handle. A tvs1900 for an LSA can be had pretty cheap. find a low mile 6.0l or 6.2l with square port heads and you could have a set 650hp motors for fairly cheap. There are many options with LS stuff you need to figure out what power you want, and comfortable putting through what ever drive you plan on running. They will probably be the limiter for what power you can make. if you want 1000hp LS motors they can be done and be reliable but it wont be cheap. What are your power goals?

Yes, they are all physically the same size. The Iron block 6.0 is 75-80lbs heavier. The LS1 is a good platform but has a smaller bore then the 6.0 or 6.2. The stroker kits cost the same but the 6.0 base yields 408" and the LS1 only 383. Most of the really good flowing factory heads won't fit on the LS1 because of the small bore. Done right though, a pair of stroked SC'd Ls1's should be in the 600hp range which would probably be a lot of fun in your Scarab!

Subscribed.

One of my favorite reads for anyone questioning the durability of an LS engine http://www.hotrod.com/techarticles/h...g_bang_theory/

Pretty much what I know, the difference between marine and auto engines is tolerance. Marine are set up "loose", and water pumps/ cooling. But also remember marine engines are always under load, compare to automotive there now. Take that hot rod mag article and see what happens when that 5.3, or ended up being a 4.6 or something, engine is held at WOT for 10 min.........

4.8l LS, 1200 HP, 26 psi of boost, 60 dyno pulls, no sign of wear at tear down. Care to try that with your marine engine?

Not saying that 26 psi on this engine is a feasable everyday solution for the boating world, but it is no secret that an LS engine is a great platform. This article proves it.

Currently a 70 mph boat. I want to be in the low 90 range

So with that being said I have no idea how much power it will take I currently have bravo 1 drives

I know LS engines are remarkable. I have a couple in my Caddy's ;)

If you ask me I would love to see a couple LS6's in a boat. :party-smiley-048:

http://www.caddyinfo.com/05%205.7L%2...V-LF%20LoR.jpg

I can't speak to a boosted LS...but I've put an otherwise "stock tolerance" ( lol ) LQ4 into a boat...and kept it pinned to the wood for 15 miles down the river.

It held up better than the "marine" 454 did...

But what do I know, compared to guys who have zero experience with an LS in a marine application? :whistle:

^Yes^.

Have been using automotive crate engines for over four decades. Other than the obvious,marine carb,alternator and starter, installing brass plugs and cams more suitable for marine use, proper break in like 20hrs prior going to WOT, maintenance is the most important, like changing oil @ 50hrs at the minimum and the engines will live as long as the so called 'marine' engine.
When I did a project with a friend, chose the ZZ572 automotive crate engine for a single engine install in a rather large boat. Needless to say, nay sayers doomed us from the beginning,lol. We have close to 400hrs on the engine running hard in the ocean,crossing between the mainland and Vancouver Island on weekends.We've encountered problems with the Stelling headers, with the inner wall cracking at the flange, dousing an exhaust valve, dropping it. We tossed the headers and had Eddie Marine make a tall s/s risers for the EMI alu cast manifold, combatting reversion with the wet exhaust system. Not a problem since.Here's the link of the build if anyone care to read it.
http://www.riverdavesplace.com/forum...ead.php?t=4456

We have 105,000 miles on the LS1 in our Corvette. Still hauls ass, still gets close to 30 m.p.g. on trips, and uses zero oil (Mobile 1 5w30) between changes. The LS1 makes about the same H.P. as my 6.2 MPI iron Mercruisers but I'll bet it weighs several hundred pounds less. There is no easy way to get more H.P. in the 6.2s but the LS1 is just crying for bigger heards and a slightly bigger cam. 400+ H.P. comes fairly easy. Add the additional cubic inches from the LS2 or LS3 and you have even more power and no additional weight. The LS7 in my Z06 was scary fast. I can only imagine a pair of those in a 29 Scarab or Fountain.

shows what I know.. haha!! Good luck! :lolhit:

Your boat seems to run well for that hull and power.(most seam to run around (65-68 gps) It seams that it takes around 475-500 per side to go around 80mph. I thought I remember it taking around 650hp per side with a -2 shorty to low 90's I read about a 29 sometime ago with procharged 434 sbc's for some reason this hull seams to be sticky, and pretty heavy also I remember that it got squirrely around 85 ( I was looking in to this same set up if I bought one but I went a different route)

It gets alittle silly at 70 but im using stock sloppy ars steering as well so tha could be alot of it. Whats the bravo 1 capable of safetly handling? Im very good with maintaning everything but whats to much? I wanna do the boat over the winter and play over the summer not be out blowing drives and screwing around.

FYI...gm holds them wide open on test stands for a hell of a lot longer than that!

FYI you willin to sell what's on the end of your boat lol

only the blue Merc engines are different internally, the standard black Merc engines have same exact internals and clearences as an automotive engine..

ls marine
 

I build a ls 2 into marine version ,got a new l 76 truck engine from the newer trucks which is a ls2 block whit ls 3 heads on it and a high truck intake ,making 360 hp

We stroked that whit a compstar kit to 408 and upgraded the valve train ,timing gear and put in a bigger cam and a ls2 intake to get it fit under the engine hatch and maked it dry sump whit ls 7 oil sytem ,cooling sytem I used from pcm .
The headers I dyno whit where cmi s but there high and didn t like the collector so switched to a set lightning .

It make s 560 hp @6100 rpm and max tq is 550 ft lbs @4700
and tq is real flat from 3000 -6300 rpm above 500 ft/lbs

know have 20 hrs of use and like it every time if I go out ,this engine push real good and screams for more !

here are some video s !

http://www.youtube.com/user/phantomlspower?feature=mhee

enjoy .so far 96 mph but still testing props and spacers .

Ls2 intake with ls3 heads? did you mean ls3 intake? ls2 is cathedral port, ls3 is square. the power production looks good and that boat looks like it runs hard. Im working on a similar project.

Sounds awesome! Very nasty.

Oddly enough my insurance agent asked me if I had modified car engines in my boat when I got it insured

Noobie first post :whistle: Cool thread! Ive spent the past 6 years modding and beating on LSX based engines in my race car, they are amazing! Im surprised I havent seen more of these engines in high performance boats, they are light years ahead of the old gen I & II designs.

The ls3 "top end" is an upgrade to the cathedral port heads anytime your running a 4" or larger bore. The rectangular ports flow alot better and are cheap considering the price of a set of aftermarket cathedral port heads. The only drawback is the 2.165 inch intake valve and 15 degree valve angle can limit your cam choices due to clearence issues.

They are not popular because mercury has not used them. They are very committed to the bbc and would have to rework there line up for it make sense to use ls based stuff. IMO it would make more sense if there engines were ls based up to the 700.

5.0mag becomes 4.8l ls, 350 mag becomes 5.3l ls, 377 mag becomes 6.0l ls, 8.2l becomes 6.6l ls (408) different cams get you your h.o. version. 525 efi 6.6l with ls3 heads and mild cam. add a tvs1900 blower for you 600+ motor and tvs2300 for you 700 motor. these could be iron or aluminum based all the blocks are available. the price for ls stuff goes way up if you plan on an engine larger than 418, you have to have a stroke deeper than 4in which I don't like on most production blocks. Aftermarket and ls7 push the price way up and in most cases are not needed.

A thread I started last year to discuss this topic. Some interesting discussion.

http://www.offshoreonly.com/forums/g...rs-hiding.html

I agree. Very Nice!

thx guys !

It s real fun to drive and very easy hardly any chine walk up to 96 mph and what there is you steer easily out it whit the dual ram steering .

that nasty engine even get the boat to 90 mph @5000 rpm whit my big 32 maximus on it !

my next project will be a 26-28 cat whit 2 ls in the back making 550-600 hp probaly a little bigger diplacement that way I can use normal bravo xr and everything keeps in one piece and still go fast !
and not to forget pretty light weight !

This will solve your problem if you want to drop the $$$

http://www.mastmotorsports.com/2010/news-view.php?id=74

Talk to Scott. He used to work for Ilmor for quite some time. He left Ilmor and went to Mast Motorsports. He was a major part in the development of this engine. Nice guy.

Don't get me wrong the mast stuff is super nice as a matter of fact I have some of there heads going on a mile land racing 427tt motor for a rx7 as we speak. with a goal of 1500-2000hp, best heads on the market for ls stuff hands down. (I just sold a set of ETP's to go this route, Cary's stuff is top notch)( I drive a 6.0l powered 2500 I have built multiple LS powered swaps, I talk anyone who will listen into ls powered car, Im looking into a cts-v, and im looking for a 24-26 hull for a ls swap.

but for the most part the mast engine is not what this guy is looking for. Its not even where the ls will do best in the marine market especially with what people are going to spend these days. for the same money teague, croket,GT etc will eat mast's lunch. The ls stuff shines when you want to make up to about 600hp cause it can be done cheap.(production block and heads etc) add in a set of 3k+ mast heads and aftermarket block and that evaporates. I can't figure out why no one is making 450hp to 600hp ls engines using mostly gm parts. once you go past a 408cid the price goes way up for little gain.

trying to go toe to toe with a bbc is foolish imo. I would not pay the same price for a small block, when I could get a BBC make more power and torque for less money.

what size cam are you running? What are the cam specs?