Hi All- I thought I might tap into the knowledge base here on website.

A friend of mine and I are considering developing a marine engine using the LSX tall deck block so we can produce a 482-500 cu inch LSX engine. We like the effieciency, overall power curves and the packaging of the LSX block. Specifically using the LSX tall deck block for strength and displacement purposes with LS-7 heads, closed cooling, hydraulic roller cam and lifters, forged pistons, custom grind cam, FAST intake (or similar), MEFI ECM and of course water jacketed headers.

Our goal is around 650hp, 580 ft. lb., about 6200-6400 rpm redline. These engines are specifically meant for offshore boats- 30-40ft V hull or cats.

High Performance Marine engines are very specific, the tolerances tend to be looser in certain areas especially valve guides and the kind of cross-hatch in the bores. Marine engines are actually closer to racing engines because they see high load- high rpms for extended periods. One thing to be considered is that we cannot use high overlap cams because of the wet exhaust pipes and reversion.

VVT is being considered since the LSX block is set up for that. We are planning on Fuel Injection although carbed engines may not be out of the realm of possibility.

Several areas we seem to be stuck on- 1)we are looking for 8-10 qt oil pans with kickouts on the sides. Which rotating assembly- Callies, Eagle, others? Which piston? Diamond, Mahle, ?

Any suggestions from the knowledge base is greatly appreciated and thanks in Advance.

Avalon

 

Just an fyi to make things simpler.
Raylay is currently making a marine aluminum block LSx. Nice looking water jacketed a\exhaust too.
http://www.raylarengineering.com/
Crusader sells a 6.0 LSx. Not sure what pan, but I have seen an LSx marine pan with full length sump. Suspected it was the crusader.
Also a good cheap source for LSx raw water pumps, spark arrested alternators/starters, etc.
http://www.crusaderengines.com/Products/6_0.html
And you may want to consider a roots blower manifold and carb setup. That would be a real bang for the buck. A carbed 177 or 256 on a 6.0 would be a great combo at a reasonable price.

 

Garys:

Thanks for the reply.

Raylar did try an LS engine but he was ahead of the curve and has not really worked on it.

Illmor has a LSX coming out at 454 cubes and 570 hp. We are waiting on pricing but around 45,000 is the number I hear. This is a high performance engine. The prototypes went into a 35 Ft Formula

Crusader engine is not a "high performance " engine. It is more of a cruiser engine, yet they manage 375 hp out of 364 cu in. This shows were on the right track.

Supercharged- thats stage 2.

Avalon

 

Great minds think alike! I and another co-worker have been doing the numbers for the past few months trying to find the best bang for the buck setup with good low-end torque.

I think a set of standard 6.0 with Magnachargers will be more than enough to propel a mid-sized performance boat. Something that makes 450-500+ ftLbs at 2500 and up. Also spin it to 6K max to keep it alive.

Our goal is to target the guys out there that have 25-35' Fountains, Donzis, Bajas, Etc that want to take another step up in performance wihtout spending 20-50k/side.

If you look at how many carbed 350,454, 502s there are out there, not even including the Mags, there is a huge market to be able to shoot for. Lots of guys with worn down power and boats that arent worth the big $$ to put new Merc Race power into. Most of those boats run with 300-400hp and no crazy torque numbers.. Anything in the 500hp/500tq range should be sufficient to give those guys a big bump in power and reliability for under 10K/side. The large portion of that being the power adder..

Keep the information coming!

 

I sold boats for a dozen years getting out of the business 2 years ago. I sold boats with ls engines since 97 starting with ls1's which were terrible in boats due to no torque down low where you need it to get a boat on plane (1500-2500 rpm) all the way up until 2011 when we offered the lsa (556 hp) which was the opposite , ***** the size of grapefruits from off idle up to redline.

look at what Indmar has done with them as they were the first to offer ls engines as a production quantity option. If your looking to test mule engines look at direct drive or v drive boats for simplicity/durability then bring them to the offshore boats once you get the power packages shaken out , I also sold Fountains 27 up to 47 feet with 4 lysholm superchargers 2 each engine (Merc racing 1050hp's)and am a graduate of Fountain performance driving school.

Reggie Fountain is no longer with fountain and has RF boats , he is the man when it comes to bringing innovation to v hull boats , if your serious I bet I can get you on the line with him with a couple calls.

someones going to bring lsx to offshore its a match made in heaven hopefully you beat the big dogs there because i am sure they are on the case , when I spoke with the gentlemen from raylar last ( 3 years ago) they were talking about penske/ilmor and what they had brewing after buying Master Craft boats

 

Murphinator- The reason the early LS engines were not good for marine use was the lower displacement. Marine engines need torque, lots of low end torque. Thats why 454's and 502's are so good. The LSX tall deck will give us displacement in that category.

When you forced induction these motors that gets rid of this issue. But you build up a lot of heat and thats a reason why we are looking at the iron LSX block. It is thermally stable and meant for high output.

Our ultimate goal is a 850-1000 hp supercharged or turbocharged application with an LSX block. It will package well, be more fuel efficient and lighter weight than a BBC.

I am hoping for those that have worked with LSX blocks and LS7 heads to chime in with their experience.

Thanks

 

Personal experience says not entirely on the first part and absolutely on the 2nd part of what I quoted.

The ls1's we sold were the corvette engine soup to nuts including corvette script valve covers lol but with indmars tune via mefi4 and indmars stainless marine manifolds , they were marketed as 375 hp , in the exact same boats you could put indmars "monsoon" 5.7 with 340 hp and 387 ft lbs which was a traditional gm sbc with center bolt covers iron block and heads so over 100 pounds heavier than the ls1 and both 5.7 liters (346 vs 350) the traditional sbc made more useable torque to plane the boat as well as midrange even with its weight & hp penalties , it was night and day in a big wakeboard boat with 10 people and 1500 pounds of water ballast in it, it was a knife to a gun fight , the ls1 as installed in a car vs a marine engine developed from a 320 to 325 to 330 to 335 to 340 hp version all under the monsoon name over 15 years.

In a barefoot boat where your running in the upper rpm's the ls1 was the better engine.

With what your looking to do the better engine architecture and added cubes will be the best of both worlds.

I was also able to compare the same boat with indmars 8.1's vs the Lsa small block supercharged and that Lsa just rips no comparison, if you can add cubes,lsx architecture, and forced induction without breaking the bank there will be customers but if your doing this as a business venture figure out where the hulls are in greatest numbers that can benefit from your efforts rather than focus on the high performance boats as the numbers are much smaller than other segments that put high performance engines in their hulls to meet customer needs but not "performance boats" by definition.

Before the market tanked back in 07 or so the store I worked at 3 of us did 18 mil in sales annually with close to equal dollars in Malibu water sports boats ,cobalt premium runabouts , and fountain high performance boats fountains numbers were under 20 units , cobalt around 50 units and Malibu around 100 units , I mention this to make you think about where the potential homes may be for your engines- dollar volume can be good in high performance but the quantity of engines is better elsewhere. You want transoms to install your engines in - you can always prove your performance reputation in specific sponsored or "team" boats but keep your options open as to where your bread and butter comes from lol

The repower market that you mentioned replacing all the 454&502 packages is likely your best entry point though as you can market those to the end consumer yourself whereas cracking into the Oem supplier chain is much harder as they are pretty well tied up with the likes of mercruiser , Volvo Penta , indmar ,PCM ,etc...

 

Im guessing your familiar with these guys by now but just in case heres some neat ob's with LS power

http://www.seven-marine.com/


Murph im curious what are you working at now? I find toy sales to be a massive indicator of the real economy no matter what the dow is doing Toys first, vacation properties next. Sorry to hijack, im merely curious and a giant boat fan too so im in for the discussion/lessons.

I cant say much about LS7 heads personally, but I do know you have to be careful with the valvetrain selection. A lot of problems in that area. In fact you might be best to start with the LSA head and CNC them. They are a very strong casting using a harder, denser alloy with a thicker deck and you will only need to profile a set of cams once as they also make decent boost heads. There are some excellent CNC profiles out there for porting the LSA heads now as well. In consideration of max durability a 6 bolt conversion might be a better way to fly though in which case your not using OEM parts anyways.

MAST black label heads are also an excellent choice that will get you away from the LS7 castings. Which i would probably avoid considering the issues that have come up with them.

Sounds like a fun go regardless.

 

I was at the Miami show when the 7 marine outboards were introduced - nice engineering

not to get long winded and jack the thread but I worked 2 states from home (ME to MA) and commuted daily most of my time in the business (86 miles 1 way) but the cost to commute vs income with the economic downturn made it not worthwhile anymore , they have tried to get me back but I still dislike what I see economically and cant sell anywhere else as I had to sign a 10 year non compete so I am working in a factory and do some non sales marine side jobs for 2 previous employers to keep the bills paid

 

I see thanks for the info. Best of it all

As for the marine7 stuff? Yeah sure is slick

 

We pulled the 502MPIs out of our TMS Formula with the intent of going LS but ran out of available time to make it happen. We ended up putting together a pair of 509s instead so we can get it back to the poker runs but REALLY want to get into the LS motors in big boats.
Not sure where you are on the project but we would love to work with you on the LSx idea, We have done our LSx motors in big airboats where the torque was needed to be instant and low RPM with great success. Some of the boats are close to 6000LBS single engine flat bottom and running on dry ground. I know we can make the TQ needed to get them going and can definitely make the power needed to pull them on the top end.
Let us know if we can help in any way making this happen. It definitely would be exciting to do. I would love to see something that makes the kind of power we are making out of the big blocks but does not burn 1.2 or 1.4 gal/min like we are doing now.

 

Cam- thanks for the tip on the LSA heads- will take a look. The 6 bolt configuration is a great idea for boosted application.

Thompson- thanks for the info.

Murphinator= Interesting info. We are hoping that by using the LSX tall deck we will be producing a lot of low end torque by being around 482 cu in.

Avalon

 

I have seen the Seven OB and they are huge. Also pricey. About $ 60k+ each.

We are not competing in the OB market.

We are looking at the engine replacement market. There are ALOT of Mercury 502 525 Hp engines out there and owners who have to rebuild or upgrade.

Mercury wants $ 30,000 for 525 HP engine only.

I want to market a lighter weight, more efficient, higher performance engine for that price. It will bolt right in and the owner will go faster with more hp.

Avalon

 

LSX block 450ish CID, Callies rods, Diamond pistons, stock GM crank, WCCH cnc'd LSA heads, FAST102 intake & TB, 236 range cam ( marine cams I know little on ) but that will put out 525+ range with ease and stick together very well.

Add a pair of 72mm turbos and LOOOOOOOK out!!! 1200 horse range should be reachable and run safely without too much concern of breakage. You'll need race gas for that though

 

You'll have a good market here in at lake of the ozarks. Lots of older sport boats needing 454s, 502s, 540s, etc.
You will be up against some small/mid size engine builders that have a pretty good reputation with their own builds at a fraction the cost of Mercs motors. There's one place here in St Louis that builds a pretty popular carbed 502 with a 256 blower.
Not being known like Merc, those will be your competition. The potential of the LSX platform is pretty appealing, but lots of old school competition out there.
I always thought a package marinizing the relatively cheap LQ4 with carbs (FI tends to be intimidating to a lot of "carb" boaters) and a 177 blower (about 1/3 the price of a LS Magnuson) could make a great, cheap 500hp motor that could compete with 454s and 502s. Only problem is lack of reasonably priced intake manifold for a roots SC on an LS motor.

 

What is you plan for valvesprings? I am not sure how the LS valvesprings will do when they are held at 5500 for a few hours at a time with valves as large and heavy as the ones in the LSa heads. You will most likely have to put springs on the motor every season to keep from dropping a valve.

 

are you planning on offering all your ls packages with closed cooling ? all the ones we sold had closed cooling standard , when I asked Indmars tech guys they said aluminum heads or blocks meant automatically it needed to have closed cooling to stave off corrosion.

 

Heres a guy I know with his LS1 jet boat rockin down the maumee!


Specs of boat can be seen here;

http://www.planetlsx.com/forums/showthread.php?t=5020

 

i work for a nautique dealership in nj. they have been Pleasurecraft marine has been putting lsx's in nautiques since the mid 2000's. started with lq4's at 375 horse from the factory. now they currently have 2 6.0 liters and a 6.2 supercharged rated at 550 hp. same supercharger set up thats on the lsa. a lot of the parts i have been getting for my lq4 chevelle i have been buying marine products from pcm. they have a pretty awesome closed cooled header set up on their "xs 550" you should check out.

 

this is true... lol