1992 omc 5.8L cobra performance mods? are there any?

[ktmracer21]

ok, so i have searched forever and haven't come up with much on adding some ponies. my boat is 92 four winns horizon 200 with the 5.8 omc cobra. now, i dont have any complaints other than im a speed and horsepower junkie. As much as id like to just buy a big block boat, i just invested in acreage so no new boat for a few years. what, if any, are proven HP adders for marine 5.8s? If you have used a part, a detailed description would be awesome. Heads? cam? intake? just build a stroker motor? I'm intrigued with the idea of a sleeper boat.

thanks!

 

[vasy]

Just look into any car website how to get more power out of that engine.
Probably way more suggestions then the boat forum. Just remember that you will also need to change gearing in the outdrive if you and anything significant and a new gear set is hovering around $1000. I believe your best and most economical way would be to buy a boat with more power.
And remember, a bit more power in the boat = a lot more fuel at the pump, not just a little more.

 

[Sparkinator]

Not much you can do cheaply on a Ford. If you try a more aggressive cam, you can end up hydro-locking your engine. Increasing the duration on your inlet/outlet valves, and if your outlet is still open during your intake stroke, you can suck water into your cylinder. GM has Vortec heads that are a fairly easy and instant HP gain, but Ford, not so much.

I've pretty much given up on HP gains, and just looking for longevity on a now 20 year old engine/drive.

 

[ktmracer21]

i figured it was worth asking. the boat was too clean to pass up in the first place and was never touched other than basic oil changes and winterizing. the kick in the ass is im currently *80k poorer....wouldve bought a nice go fast! thanks for the responses.

who wants to buy a spotless open bow?!?!? haha

 

[Redrig]

GT40 heads will add some HP and effeciency , and can be used with your manifolds . Thats on my list anyways.

 

[Bondo]

Ayuh,.... Short of Strokin' it out, nothin' bolt-on is gonna kick ya in the seat of the pants,......

Takes alotta Horsepower to move up a couple inches of prop pitch,...

 

[skippy2235]

My suggestion is add a NEW fuel injection system.
there are lots of options.
I did the DIY Megasquirt system, Works awesome. I love EFI
However with the added HP, my drive failed, the OEM cobra drive is only rated at 250 hp and weak.
So if you upgrade the HP on the engine, you will need to upgrade the drive to a Mecruiser Alpha 1 gen 2, rated for 300 hp.