engine horsepower question

[jutebox2000]

I am looking at a boat with a cobra outdrive and has the following engine.

4.3 Liter Spitfire H.O. 230hp

I would like to know what H.O. means, and also how to get 230hp from a 4.3 litre engine.

 

[Frank Acampora]

Re: engine horsepower question

H.O. stands for High Output and that's how they get 230 HP out of 4.3 liters. Probably a hot cam, larger valves, larger throttle body or carb and/or different computer chip and fuel injection rates

Actually, that's not a lot as the 4.3 in my stock S10 is 190

 

[Fisherball]

Re: engine horsepower question

I had a Buick Park Avenue with a 3.8 that had 230 hp. It was supercharged & needed premium fuel but ran like a bat out of hell. A blast to drive a big beast with that much power.

 

[Knightgang]

Re: engine horsepower question

Yep, High Output... You will be very surprised at how many horses they can get out of engines these days with just a few minor changes...

 

[Silvertip]

Re: engine horsepower question

GM has built many engines over the years with 1 HP/cubic inch. So theoretically the 4.3 (262 cu. in.) could see 262 HP in normally aspirated form. The GMC Syclone/Typhoon pickup & SUV had a turbo charged 4.3 and although they were conservatively rated at 280 HP, they did show over 300 HP on a dyno. The Buick Grand National GNX with the 3.8 Turbo (231 cu. in.) was 276 HP.

 

[John_S]

Re: engine horsepower question

Crank rated HP? vs prop? If so, lop 30hp off and you are back in the reasonable range.

 

[Silvertip]

Re: engine horsepower question

We are talking 20 year old cars with very ancient ECM's. If those engines were built again today with the more advanced engine controls they would likely see much higher output than they did back then. Those engines were rated SAE Net meaning with all accessories. And those vehicles were also saddled with emission controls that aren't included on the 4.3's in boats.

 

[TilliamWe]

Re: engine horsepower question

4.3 Liter Spitfire H.O. 230hp ...

Yeah, that 230 is at the crank, which means 200 at the prop, that's normal.

But somewhere in my little skull, that word "Spitfire" is sreaming out RUN AWAY! I am 95% certain I read it on here, that "Spitfire" is a reason to run away screaming. Also, if that engine has the one piece "batwing" manifolds, that's bad too. Not to mention it's an OMC Cobra drive that is obsolete, from a company that doesn't exist any more. But hey, have fun.

 

[Bondo]

Re: engine horsepower question

I am looking at a boat with a cobra outdrive

Ayuh,.... Keep Looking,.... You don't want to buy an OMC anyways.......
They went Bankrupt 13 Years ago.....