Date: 8 Jun 1997 05:33:18 GMT From: "Daniel J. Hunter"
Newsgroups: rec.sport.waterski Since you are out there listening, how about answering a question or two? What is driving the current horsepower race? Obviously, there's some demand but is there a real purpose? Let's take a look at two of the more popular engines offered by Mercury Marine to illustrate my point: Mercruiser's 350 Magnum EFI Propshaft Horsepower:290 Maximum Peak Torque:365 Ft. Lbs. @ 3,800 R.P.M Compression Ratio:9.4:1 Fuel System:Mercruiser/Delco EFI Full Throttle RPM:5,000 Mercruiser's Black Scorpion Propshaft Horsepower:315 Maximum Peak Torque:365 Ft. Lbs. @ 3,800 R.P.M Compression Ratio:9.4:1 Fuel System:Mercruiser/Delco EFI Full Throttle RPM:5,000 I noticed the same peak torque (occurring at identical RPMs) on the 350 Magnum EFI and the Black Scorpion. Does the difference of 25 horsepower result in a measurable increase in performance that might justify the additional cash outlay? Have you done side-by-side tests comparing the relative performance of your power packages and will you publish the data? Is it correct that the Black Scorpion is the only Mercruiser that requires premium gas, a drawback of the maximized total ignition advance setting? After years of operating smoking outboards, I am thrilled to see the wholesale adoption of fuel injection. Still, tournament boats have been embroiled in a horsepower war that has failed to significantly increase top end speed. It appears that tournament boats are essentially semi-displacement hulls with a limiting hull speed. If this is the case, it would be interesting to note what those speeds are. Boats designed for barefooting continue to use outboards with a significant CG difference and hull design so apparently there is a limit to how fast a tournament hull can be pushed. Any thoughts? Hunter
Date: 10 Jun 1997 13:26:00 GMT From: Dan Hoffmann
Newsgroups: rec.sport.waterski The current issue of WaterSki magazine has a very interesting boat test of a Sanger inboard with four different Mercruiser powerplants, starting with the 350 carbureted, up to their big-block Super Scorpion. Interestingly enough, in this test, acceleration didn't change dramatically from the 290 hp but top speed did. Mercruiser was allowed to pick the props and the 377hp SS went 56mph. The only thing missing from this test was a measurement of fuel economy. This article shows that contrary to what many in this newsgroup say, inboard ski boats can run well into the 50's with brute force and the right prop.... Dan
Date: Wed, 11 Jun 1997 09:51:20 +1000 From: Daniel McCurtayne
Newsgroups: rec.sport.waterski The lower the noise, the lower the performance. The more fuel economical, the lower the performance. So if you want less noise and more fuel economy, don't buy an inboard. Noise is part of the sport, deal with it. DAN P.S. I lover the sound of a roaring V8 boat. Dan Hoffmann wrote: > Please note that I didn't advocate high speeds nor assess any value to > > them. I don't even barefoot. I was only pointing that inboards CAN go > pretty fast if that is desired. The two things I'd like to see from > manufacturers is better fuel economy and less noise. Better fuel economy > saves me money. Maybe boat makers need to juggle their props a bit more > instead of staying with 13x13. I just don't enjoy noisy motors.... > > Dan >
Date: Tue, 10 Jun 1997 20:37:49 -0400 From: Mark Kovalcson
Newsgroups: rec.sport.waterski Daniel McCurtayne wrote: > The lower the noise, the lower the performance. > The more fuel economical, the lower the performance. > > So if you want less noise and more fuel economy, > don't buy an inboard. > > Noise is part of the sport, deal with it. > > DAN What an attitude !!! The noise bothers me more than the fuel economy, but I would spend at least 1,000 dollars for a noise cancelation system that dropped the noise levels by 10dB or so. Many people comment on how much they like the sound of my 240 Hp PCM with glasspacks. I'd prefer quiet !!
Date: 10 Jun 1997 15:42:33 GMT From: Reg_Burgess%AntiSpamPostfixemail@example.com Reply-To: Reg_Burgess%AntiSpamPostfix %@stratus.com Newsgroups: rec.sport.waterski In article <firstname.lastname@example.org> "Dan Hoffmann"
writes: > This article shows that contrary to what many > in this newsgroup say, inboard ski boats can run well into the 50's with > brute force and the right prop.... Yes, but why would you want to buy a "Ski Boat" to use as a "Speed boat" ? Dunno 'bout you, but I have NO desire to ski or foot at 50 +
Date: 11 Jun 1997 03:15:56 GMT From: kevin R Baugh
Newsgroups: rec.sport.waterski Dan Hoffmann wrote in article <email@example.com>... snip > This article shows that contrary to what many > in this newsgroup say, inboard ski boats can run well into the 50's with > brute force and the right prop.... The Sanger is not a typical inboard ski boat it has much more v almost all the other inboards ar flat in the back the Sanger is not..
Date: Thu, 12 Jun 1997 12:02:43 +1000 From: Daniel McCurtayne
To: Dan Hoffmann Newsgroups: rec.sport.waterski Dan Hoffmann wrote: [snip] > I want less noise > because my boat will have kids in it and I'd like to talk to them > while > we're underway. So how can you talk to a kid while they are skiing if your in theboat and they are skiing. When I'm skiing with a friend I can hardly hear what they are saying and they are only 1-2m away from me, this has nothing to do with engine noise just the fact that the wind past your ears is too loud. > I'm not looking for a silent inboard boat, just a bit > quieter than most are today. > > if you had read the original post, you might have noticed that the writer > asked manufacturers what was driving the horsepower race. I merely suggest > that engineering could be spent on some things other than hp. Do you know > anything about engines? Yep, as much as I need to know at this point in my life. > Most of the EFI engines today have better economy > AND performance than their carbureted versions.... So thats why drag cars and drag boats are Fuels injected, not Blown. Nothey would never thinks of putting a blower onto a drag boat. > Most high performance > engines, whether boat, car, or motorcycle are actually more efficient > with > a given quantity of fuel. I don't know what you are saying here but I know thatAv gas ain't cheap. > If you take the muffler off your car, does it > produce more power? Do you mean muffler or exhaust pipe.If you mean muffler, when you take it off it doesn't increse performance but a muffler is designed to reduce noise, not performance. But if you put a bigger exhaust system on, THAT increases performance and noise. > Nope. All aspects of engine performance are tradeoffs > and can be balanced in almost any direction. @*X@!!!, so many mods can be made to an engine its notfunny. A lot of them increase performance and don't have an opposite effect, you are just making a generalisation here. DAN > Dan > > Daniel McCurtayne wrote in article > <339DE877.1E03934F@viper.net.au>... > > The lower the noise, the lower the performance. > > The more fuel economical, the lower the performance. > > > > So if you want less noise and more fuel economy, > > don't buy an inboard. > > > > Noise is part of the sport, deal with it.
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