1994 Four Winns 190 horizin 5.0 cobra engine swap & upgrade

[Efini Motorsport]

Have you done a compression and leak down test on the engine? I'd start by figuring out where you stand now with the current engine.

 

[HT32BSX115]

any ideas as to what cam will go good with the fuel injection

Not a LOT in an application that requires a max RPM of about 5000-5500 RPM or so.

If you want more power in a stern drive application, you need more cu inches.

Now, you did not reveal what you have. You either have a 1994 5.0L FOMOCO engine and Volvo SX drive or you have a 1993 5.0L engine and a OMC Cobra Dog-Clutch drive.

Very good advice was already offered.

With either, you can scrounge the parts required to switch to a CHEV 5.7L (series) engine and either drive will perform well with that engine and you could even upgrade to a stroker engine and both drives have been shown to work well also.



If you try to run an automotive engine that makes hp at 6000-7000 RPM it simply will not work with a "regular" stern drive. And if you try, that stern drive will not survive long.

now if you want to go to something like a Mercury racing or similar drive or a surface drive, or a jet, you can do all sorts of things.......JUST ADD copious amounts of $$$

But who does that sort of thing with a recreational family boat?


Also, you can put all sorts of illegal "stuff" on a boat that violates the USCG regs and ABYC guidelines and no "boat cops" will probably ever inspect it and cite anyone.

But when it blows up with the neighbor kid inside and that kid is crippled for life or dies, The family "Slip & Fall" Lawyer(s) will not only find out whats under the hood, but during "Discovery" will have copies of all the public forum transcripts of how the owner was negligent , KNOWING that what he/she did was not only illegal and non compliant but "resulted" in death or serious injury........

After that, the poor "chilln's" lawyer(s) and family will own the boat owners house, 401K and any other assets he or she had.

Some insurance companies actually have disclaimers for illegal modifications, and of course all have limits on liability even if you have "blanket" multi-million coverage....

Eyes wide open!! :thumb:

Rick

 

[Efini Motorsport]

My BMW engine redlines at less than 7000. Very few cars are much above 6000. Trucks would be even lower and jj50, you're on the right track sticking with a truck or towing style cam. You want as much torque as low in the revs as possible and with as little overlap as possible to stop water getting sucked in. I don't know if there's a on you can get out of a cam that will help you're hole shot. I'd definitely start with a compression and leak down to see if it's even worth doing anything on that engine. It may just be worn out. If that's the case a 5.7 swap would be probably be cheapest and easiest. Everyone knows chevy's are better than ford's anyway.

 

[HT32BSX115]

If that's the case a 5.7 swap would be probably be cheapest and easiest. Everyone knows chevy's are better than ford's anyway.

Fords would probably be just fine if the Marine Sterndrive "world was still using them..... Merc and Volvo abandoned FOMOCO in the mid 90's, and OMC went out of business.......

You can still get Ford inboard engines in certain Ski boats, but they're not stern drives.

If the 5.0L is not worth fixing, switching to a GM 5.7 or 6.2 etc would probably be best bang for buck.......

 

[Lou C]

I love fuel injection in my vehicles but in a older boat, the issue is parts availability and repair-ability. On these engines with the simple roller lifter camshaft you are not going above 5,000 rpm ever, and more typically if you want you engine to last, 3500-3700 or so cruising speed is what you should shoot for. They are not like modern outboards with dual overhead cams and 4 valves per cyl that can run at 4,000-5500 routinely. If you run your I/O that way it will not have a long life. They are not designed for it and the limiting factor is the durability of the valve train. The roller cam and lifters on the GM engines helps a lot, the wear is much lower on them than on the flat tappet cams and the small block Ford as far as I know did not use a roller cam in marine applications. So if you stick with a Ford, stick with a Holley 4160. Holley actually still sells the one calibrated for the 5.0 and 5.8 Fords brand new.

 

[Scott Danforth]

here is my take. a boat is like a dump truck stuck in 4th gear with a load of sand driving up-hill in sand. only torque matters at that point.

BMW motors have no torque, so what is the point of bringing it up.

stock outdrives cant lubricate themselves above 5500 RPM without modificatation, so what is the point about talking about 6000 RPM

ford 5.0 marine motors are a mix of 5.0 block, custom crank, 351 marine cam and for many years, the GT40 heads

automotive EFI relies on O2 sensor feedback - not available in a boat without custom manifolds

automotive electrics do not have the require J1171 compliant tag. doesnt matter if they are the same part, without the tag, its illegal in a boat.

non USCG approved fuel systems are illegal in a boat.

bottom line, if you want to stick with ford power and you want it to go fast, build a stroker windsor in the 6.2-6.5 liter range

 

[Efini Motorsport]

I only mentioned the BMW because HT32 mentioned 6-7k RPM's which is high for most engines. The dump truck analogy is a pretty good one. Marine use is pretty hard on engines and have a small operating window. I'm actually using o2 sensors in my build. I can because the new style manifolds I swapped to have a port that will work for them. Having o2 sensors makes tuning much easier but it is possible to tune via speed density using mass air, intake temp and manifold pressure sensor. Many race cars run this type of system and almost all of them use standard GM parts for the sensors. In todays open source world there's tons of tuning options available for almost anything. For now I'm running the stock GM intake manifold and fuel injection setup but I will probably swap over to the merc setup next year. It is a straight swap that is done on the vortec truck motors as it flows better and uses a standard injector instead of the funky vacuum spider GM used on the trucks. It is also USCG approved.

 

[jj50cal]

Efini Motorsport, ok great, i have no experience with the fuel injection systems, my son loves them but has limited experience also, like i said earlier, i am an old skool gasser, mouse motor (327) holley 750 dbl pump with comp cam with 520 lift, and 480 duration, pullin around 420hp in front of a turbo 400 tranny, and 411 gears all wrapped in a 68 chevelle body. thats where my experience lies. i have or we have several boats that we manage to keep afloat and running most of the time. everything from kawasaki 900 and 1100 jet ski's, 1986 mark twain w/ 140hp chevy mercruiser 4cyl, an 85' chris craft w/ same set up, just a lucky coincidence, and the famous 94 four winns. the biggest trouble we have with the four winns is that the motor seems to always be draggin during start up, as if trying to use a 6 volt battery to crank with. we normally change out the starter because of the dragging twice during the year, my rebuilder probably thinks i'm bring in cores and having him build them under warranty, lol.. if i didn't know him i might be suspicious of his wermanship, but i know him well and he knows i wouldn't do that to him. i have even tried a brand new starter that i purchased from the boat dealership here in memphis that carries omc parts, with the same results. hence why we are starting to think the motor is just tired. We were tossing the idea of just swapping the heads out with the mercury 5.0 mainly so we can actually change spark plugs without pulling the exhaust manifolds off to get to them. the person who designed that should be drawn and quartered and hung upside down. anyway, it was my suggestion that if we go to the trouble of head swapping to just go ahead swap it all, since we have to pull the engine anyway. easier to do it on a bench than humped over.

1963 GlassMaster w/1965 65hp Mercury
1984 Mark Twain 160 w/140 mercruiser
1997 Kawasaki 1100 JetSki
1998 Kawasaki 900 JetSki
1994 Four Winns 190 Horizon w/'94, 5.0H.O Cobra and 93cobra flattop
1984 MonArk 17ft, w/75hp mariner

 

[jj50cal]

ok guys, this is all very helpful, thank you.... we are NOT looking to build a bomb. if we were, i know exactly how to go about that, and it would be SOOOOOO, much easier and cheaper. LMAO. now to be serious, the original original 5.0 by the FIRST owner was a 1993 5.0 H.O. Cobra 4bbl. but he failed to winterize it, and it cracked the block. so the dealer put a NEW 1994 5.0 H.O. Cobra 2bbl engine in. all according to paperwerk. my son found out thru his research that the fuel injection was an option on this boat as well, hence what he wants to do to it. but since our last discussions, compression is good, 120 to 128 in all cyclinders. no leakdown to speak of. (lost about 1pound in 3 holes in an hour), but we have all but decided to just pull it. and start from scratch. now that being said... my options are: 2001mercury 5.0 HO.? 5.7 FOMOCO w/ tow/marine camshaft,? (already have these), or bite the bullet and purchase new 5.7 or 6.2 chevy and install a big ass tow/marine cam. if i gotta buy a new one (gonna make it thump) at least then i get something out of it....

1963 GlassMaster w/1965 65hp Mercury
1984 Mark Twain 160 w/140 mercruiser
1997 Kawasaki 1100 JetSki
1998 Kawasaki 900 JetSki
1994 Four Winns 190 Horizon w/'94, 5.0H.O Cobra and 93cobra flattop
1984 MonArk 17ft, w/75hp mariner

 

[Efini Motorsport]

If you're going to drop in a new engine anyway check out Michigan Motorz and a few others that offer brand new turn key marine LS based motors. They drop in and include fuel injection, computer, fuel pump, etc and are specifically for marine use. If I had a v8 I would have gone LS in my swap but I only had room for a 6 without cutting the boat up pretty good. There's always the next one though.

edit: Michigan Motorz isn't the companyI was thinking of. I know I've come across a few places that offer full packages though.

 

[Lou C]

If the fuel lines were ridiculously long I could see that being an issue also. The coast guard doesn't seem to have any regulations about fuel hose length but again you need to use common sense. The statues specifically says "in a straight line from pump to engine not following the lines." If they are that close it's hard to get crazy with the amount of fuel line.
My fuel pump is an in tank but does not run through an oil pressure switch on purpose. The engine computer controls the pump and kills power to it any time the engine shuts down for any reason. The pump is made to mount in a plastic fuel cell (which is what I have) and has a threaded lock ring that goes in the tank and sandwiches the tank, gasket and pump flange together. They are made for racing environments with the potential likely hood of being subjected to high g loads in a crash. If I had an aluminum tank I would have welded in a flange ( and yes I know the tank needs to be purged for welding so I wouldn't be making a bomb there either.
I don't know about all "marine" alternators but many of the new ones I've seen have the same vented case design as what I'm using. I do know they used to use screens which everyone knows a porous mesh is the best thing to keep fumes out. In conversations with the electric motor rebuilders and an electrical engineer with decades of marine experience I feel pretty confident in using the automotive parts. I can't even find one case in online searching and in talking with any of the dozens of marine shops we deal with of anyone actually blowing up from using automotive parts.
I did a quick search for marine alternators and came up with this Balmar alternator (part # 260757) which lists for $962 from defender. This is what most of the new alternators look like, with a very open case design and internal cooling fan. There are no screens anywhere on it. If gas fumes are present they will get inside the alternator screens or not. The only way to make them marine is to seal the things that could spark, the brushes and commutators. I've never even found a good explanation as to how a screen is going to stop gas fumes except for potentially grounding sparks before they could ignite fumes OUTSIDE the alternator. If fumes INSIDE the alternator get ignited a screen isn't going to prevent the flame from traveling out and igniting any fumes present outside.

Ok the way the screens work is just like a flame arrestor. If there is an explosive atmosphere and it is ignited by a spark the screen prevents the flame from traveling. It. Is not to prevent fumes from reaching the source of the spark. So in this case you have an explosive atmosphere and the fumes get into the alt or starter or distributor. The screens prevent any flame from leaving the alt, starter or distributor and igniting the rest of the fumes in the bilge.

 

[Lou C]

Think about it a flame arrestor is just a type of screen, if screens did not stop flame they would not work.
This is why the are required by Coast Guard regs all inboard gas engines. If you have a back fire in the intake manifold (where a leaky intake valve allows the spark plug to ignite the flammable mixture in the intake) it will be confined to the carb, instead of spreading out beyond the carb to ignite rest of the fumes in the engine compartment.

 

[Efini Motorsport]

Never seen a fuel injection system backfire back through the system like a carb (that I have seen a few times). Not saying don't use a spark arrestor, I'm even putting one on my fuel injection setup.

 

[Lou C]

I haven't either, but I guess its possible if an intake valve hangs open, esp if its a throttle body system with the whole intake full of air/fuel mixture. With a port fuel injection system, the intake is mostly full of air with the fuel being injected near the intake port...

 

[jj50cal]

I will do some research on it, it may be the best way to go, by the way anyone happen to know anybody that is willing to put in a new wooden floor? now that I have 2 total knee replacements, I cannot crawl around on my knees. the flexibility is just not there anylonger, not to mention the pain the titanium against skin creates... I was able to cut out the old rotten floor before the surgery. but now need a pro to do it right.

 

[jbcurt00]

Closed as it seems you're going diesel, shouldnt run overlapping topics.

Discussions about the boat deck needing replacement should be in the restoration forum, not here in an engine topic.

Please also remember iboats forums dont have a swap/sell/work on my boat section, so refrain from soliciting work, keep it about 3rd parties completing the necessary deck repairs