242LS Repower with 588 CI GEN 6
 

Hello, I'm a new member, and am curious about the most powerful engine one has ever put into a 242 LS? I have seen some posts with 540's with 535HP, but has anyone ever put in say a 588 with 700HP or a blown 588 with say 900/1000HP? If so, what other mods have been done to the boat (Drives and srivetrain)..

Has anyone run Arnesons on a 242 LS? ASD6 or ASD8...?

I am trying to get as much info as I can, because I would like to get this done properly. I have a 588 in my garage, and plan on installing it soon. It should have a conservative 675HP, as the cam is mild, and the compression is 9:1

Will I need a new engine harness, or can I use the one from the 454 mag?

Why am i doing this? Well, i need another hole in my head.. No, actually, my 454 mag blew a head gasket, and the heads may be cracked.. (Don't know for sure) I then found a great deal on this 588, and bought it thinking some more power would be nice.

I know I will need a better drive, and I think maybe an XR, or IMCO SC, or alternatively an Arneson ASD6 or 8 using the Bravo Conversion kit.. However, the drive replacement can wait one more season, as i do not abuse the boat, and unless the B1 breaks, I see no need right this minute. in addition, I am not Rockerfeller.

All help is appreciated. I have attached a pic of my boat, and the new engine.

Thanks,

Richard

thats a good looking 242

Blue, did you buy this boat in the last year or so, good looking ride. What do you think for speed 75+.

there is a 242 ls in windham maine for sale with a blown big block not sure of the specs but my neighbor almost bought it. said it was 600++ maybe closer to 800 hp and the boat runs in the mid 80's on gps. but still has bennets and has blown them off in the past.

My buddy has a 509 @ 535 hp and gets 69.6 GPS with a labbed 24 B1
Here it is during the install and tested later in the day. Got towed home with a broke Bravo:(

Keep us posted on what you end up doing...that is a fine looking 242. Mine has the same paint scheme, but with black hull sides and red striping. For now I'd like to get a few more horses out of the 454 I have in mine, but if I keep this boat a while I'd be looking to repower along those lines as well.

I don't know how much power or speed these hulls can ultimately handle--have you upgraded the trim tabs? Good steering rig also a must...

Hi Everyone,

Thanks for the input. I have been chasing down some odd parts to get the motor complete and ready to drop in. My old motor is a Gen 4, so I have to get a bunch of new parts. Still looking for an oil pan, pickup, and pump. I was going to dry sump the motor, but decided to just go with a regular wet sump. I am also looking for a Gen 6 bell housing, internal balance flywheel, and HD drive coupler.

I am also in process of negotiating the purchase of an IMCO Extreme SC drive, as I do not want to get stuck out on the lake the first time out like "Mopower's" friend. In addition, the B1's seem to be only valid to 500 HP even XR's maybe to 575-600 HP. As my engine is closer to 700, I am thinking I have to do the drive now as well. I was not planning on this, but I guess stuff happens, and I now have an additional expense.

I eventually plan on external steering, or at least drive stabilizers, and an oil cooler for the drive. I was shocked that there is so little oil in hte drive to begin with.. Hell, a 75 HP Fiat has more gear lube in its diff..!

In addition, I want to dyno the motor to get a baseline, and tune the carb.. Still trying to decide on the Carb.. The motor has a 4150 intake that is match ported to the heads, and I have seen some carbs that flow 800-1000 CFM, but I think I may be able to get a deal on a 1050 Dominator, so I may have to get an adapter plate to use the 4500 series carb. More research to do....

I'll keep you guys posted with the progress. I should have some more in a week or two..

(Next time, I will just buy a new boat, it will be a hell of a lot easier than this!)

Richard

Schweitz, (Kommen sie aus CH?)

I still have the Bennets, and plan to upgrade to K-Planes, or Dana tabs.. I actually bought a set ok used K-Planes from some Yutz in Florida, and got hosed. They are corroded, and the trim pumps were broken around the casing. So, there went a buch of cash down the drain. I actually paid through paypal, as it was on Ebay, but paypal is now deciding if I have a claim or not, so maybe I get my money back, or not.

Masi,

I bought the boat last year after a 242 SR1 got bought out from under me. I actually like the single, and the extra space in the hatch. I also like the blue color the best.

As far as speed, I have no idea, and will wait and see what the GPS says. It seems that with a Hydromotive Q4 25P, the boat might get to 75+. GPS will let me know, I just want to get the thing up, and running properly. The weather is getting warmer here, and in 1 month, I'll be late out on the lake.. :)

Richard

Almost forgot... I have a set of CMI E-Tops in the garage as well, waiting on the Header studs I ordered to put them on. I will use SCE copper gaskets, as they are reuseable. I'll post a pic of them mounted once I get them on.

R

In all fairness to plain old Bravos , my buddies was low on oil and the upper seized up , twisted the spline going into the coupler and had to cut the the shaft to pull the drive then the engine again to change the coupler:rolleyes:

more engine mods
 

Hi All,

I am getting a deal on this stuff, so now I am figuring out how to make it work on my 588 CI motor.. Just a quick update on the project.

Comments...? Anyone ever try something like this before..?

Richard

Update..,

I bought the IMCO SC drive, and a few other things as in the pic above.. I also bought a full EFI kit from an HP 500, and a procharger M1 kit to go with it. I also asked AZ Speed and marine to fab up a set of intake spacers to clear the tall deck block that I have, and for a set of valve covers to clear my stud girdles.

I also ordered a Canton Offshore Oil Pan, Canton pickup, and a Melling HV pump from TP Marine... Waiting on the package to arrive. A Teague chrome crossover kit is also on the way, and waiting for those boxes to show up as well.

Still left... Bell housing, coupler, oil coolers, raw water pump, hoses, and a few knick knacks..

I also found out that my CMI headers I have might not work, as the setup is for a TRS.. So, I may just sell the setup, and get a replacement.. Anyone have a set of E-Tops they want to trade...? Or buy..? Good deal to be had...!

So, I have to bolt on all this stuff, and get the motor ready to be dropped in hopefully by the week of 5/20.. Lots to do..!

I am curious about reprogramming the MEFI controller for the procharger kit, as I want it to run in closed loop, and also read the boost from the Procharger as well... (I don't want to shell out for a Motec new, and just missed one used...) Oh well.. $$$$$$$$$$$$$$$$$$$$

Richard

Blue sounds good, now it`s time and patience putting it together.

Hi Mas,

Yes, too much time, and too little patience.. I want it all done now, but yes, I have to wait for a bunch of stuff to show up in boxes, QC it, then test, retest, then when all is good, bolt it on in the boat, then of course I will hvae to test some more while in the water.. I hope this does not take all summer....!

Getting closer though.. I have an appointment with the Tech to do the swap the week of 5/20, so I am going as fast as I can to get the motor done before that.

I'll post pics of more stuff when it shows up..!

Thanks,

Richard

I'm running 620HP in my 242LS. It's a custom built 454 (bored .060) with DART intake, heads, Holley 850, etc... I saw 70.1 on GPS last year with an antiquated Bravo 1 drive. It's now history and I'll be running a Bravo X (XZ) upper with IMCO extreme lower. I'm also getting the nasty hook taken out of the hull. I expect to see about 75 MPH.

damn thats some impressive numbers outta 242

Hi Chewy,

Interesting..! 75 would be nice indeed. I think mine went about 58-60 with the old 454 mag before it blew. I have been doing some dyno simulation with software, and I think if things are right, I should exceed your power level when all is done. However, lots to do before that.

What prop are you running? I just bought an IMCO SC, and will bolt that up to my transom as well. I think my motor will have 650HP conservatively NA, with 700 TQ across a wide portion of the powerband. After supercharging, that will go up a bit.......

Bblades said I should try a Labbed 28 Bravo 1, or Hydromotive 4-Blade prop.. Is what you are running similar?

I have not looked into getting the hook out yet.. What will that cost you?

I read on here, that someone had a blown 540 or something in a 242 that went 86mph... I thought wow... Maybe I can aim for that if i am lucky.. Then I gotta go learn how to drive this thing at that speed.... :)

Thanks,

Richard

I agree - those are real nice numbers...even 70mph is nice. How's the overall handling? I'm sure taking the hook out will help. :D

Thanks for letting us know about this...I know a lot of us 242 owners are interested in bringing our performance up to modern-day standards, and these kinds of projects give us an idea of what to expect...:cool-smiley-011::cool-smiley-011::cool-smiley-011:

Does anyone know what the maximum spped the hull can take on a 242 before it falls apart or the boat disintegrates?

The blower brackets are on order, and I am in process of fabbing a few items.. Getting closer to full mockup..

Thanks,

Richard

I wouldn't worry about that unless you have a few hundred thousand for a turbine conversion. my twin with 660hp runs high 60's 71 tops onGps 1 footers no fuell etc. And runs straight and flys nice

Well guys... it blew up into pieces. Actually all is going well. I'll be picking her up from the fiberglass shop in a day or two. To answer a couple of questions that have been asked:

1) The ride has been outstanding. I've run a couple of poker runs and it has handled some pretty nasty water with no problems. The drive didn't do too well though.

We took some 4-5 foot jumps with no issues and at WOT. I'd say it took the rough water better than any other 24 footer.

2) I'm not sure about a 28 4-blade prop. I've tried a 24P 4-blade Hydromotive and couldn't spin it like I'd like to (looking for 5500-5700 RPM) and it made the backend loose. I'm turning a 27P Mirage Plus and that seems to be what the boat likes. Running 70MPH at 5000-5100 RPM.

I'll let you know about the IMCO and taking the hook out benefits (if any).

Hi All,

Not too much progress, as I got the wrong oil pan, now need to exchange it... so that will be a few days..

Anyway, I spoke to Dave at IMCO, and good news is that the drive should live at 7,000 + RPM with the mods I have planned. They reccommend 6500 RPM and the increase I was told is ok depending on hull weight, oil cooling, and a few other things... Anyway, that's the good for today..

TORQUE is what breaks the drives... So, if you have a high RPM motor with 650 lb/Ft the drives should be fine according to IMCO.. (I should have about 800 - 850, so I need to look at ways to alter that a little bit, and or move it up the curve.)

Oil pump, dipstick, and pickup are in.. Now need some coolers, and a flywheel etc.., CMi is supposed to modify my TRS tailpipes to fit the Bravo transom.., but still waiting on an RMA # from them.......

Custom intake in process of being built... This is Exciting..! :cool-smiley-011:

R

Anyone on here actually have or know of anyone that has run a 242 with the hook removed? I'd really like to hear what the differences were. Ride, speed, and stability
Also was the hook removed totally or just partially?
Toying with taking down but not all the way.

2" shorty worked well and I think working on the bottom is the next logical step.

Hey 242-502,

I don't know anyone, but I called up the factory, and spoke to their tech dept about it, as I am in process of a custom repower.

They said that I would have to add material to the inside of the boat, but remove the plywood first, build the bottom up to how much I wanted to remove on the outside, and then add the plywood back, glass it all, and seal it up..

They did say it would gain a few Mph.. Not exactly how much, but a few... I am guessing 3-5 Mph based on the indirect answers I got from them...

After all that work, and chatting with the tech guys, it seemed that there may be an easier bit than all that work, by just adding more power for the 3-5 Mph top speed....

A racer guy told me that the boat might be prone to chine walking without the hook, and there are other ways to solve the hook issue....

Hope that helps,

R

Thanks
More to think about

formula242-502,

do you have any before and after numbers/figures with the shorty? what kind of HP did you start with and what other information about your setup can you supply. Very interested in the gains of a shorty on a stock 502 setup. Thanks

Started out at 68-69 mph with the stock lower
Ran a consistant 70-71 and hit 73 once on the GPS
I should have around 525 HP
All speeds with the same modded 23 mirage plus
I have not had luck with any 4 blade yet, but have't been able to try many either.
Boat rides flatter in shoppy waves due to less trim required.
Did have a problem in 4-6 foot waves with blowout - right 4 blade should solve that.

Pretty interesting stuff...! I have a 23P mirage on mine now, and after the repower I will test and tune for optimum prop.. My imco sc has a 1 inch shorter lower on it..

Do you have an extension box as well?

R

No extension box

Thanks,

R :)

Whatever happened to this boat? Did that monster motor ever make it in?
I hate it when a story goes unfinished....

After reading the 1st post, I would have to say that my 1st upgrade would be kevlar shorts. Because it it gets into triple digits with that much power Id have a woody made of titanium

I wondered the same on this post ......