Conference vicki::boats

re                     <<< Note 1033.0 by SALEM::NORCROSS_W >>>
>                     -< New supercharged Ski ?? available >-

>    In this month's Trailer Boats Mag they cover ten new boat offerings
>    that are being shown at the current boat shows.  The one that caught my
>    eye was a "Ski ???" (Centurion, maybe)  ski boat that has an optional
>    supercharged 351 Ford good for 400 horsepower and a top speed of 51

	If it is a Centurion, maybe the wake is low enough at 51 (-:

>    MPH.  They said the acceleration was excellent.  Another new addition

	With a blower it should be - with a turbo it probably wouldn't 
be much better than stock, in the range that matters.  For me stock is 
adequate.

>    was a front "fin" that steered along with the rudder.  They seemed to
>    really like the boat but did not comment on how it would do as a 
>    tournament ski boat, not having the chance to try it.  A steerable 

	Duhh, OK, I'm a cynic  - -  but did they just like it as 
something to trailer ?  (-:

>    front fin or rudder is a very old concept for boats that never seemed
>    to get acceptance.  I wonder why.

	Kinda like rear wheel steering on cars (newest, latest, 
greatest innovation, etc.)  But VW bugs had it all along (-:

>    Wayne

	Reg	{the silly cynic}

I saw that article on the supercharged Ski Centurion too.  I'm not sold
on it being the way to go, and apparently neither was Trailer Boats. I 
happen to have the magazine here at work today, and the magazine that 
never met a boat they didn't like, said:

"...the acceleration is exhilerating.  The practicalitiy of a supercharger
on a tournament skiboat is subject to question, however".

Some of the possible problems for a supercharged engine include:

- Excessive wear, and shorter than normal engine lifespan.  

- Limited service and parts availability. Most likely, only Indmar dealers
  will have the parts and trained staff to fix 'em.

- Excessive repair cost, should the supercharger fail

- Excessive noise

- Higher initial price. Base price for the boat with no options is $23,900

IMO, a better option might be to go with a big block Chevy 454, which will 
push boat to similar speeds without even working hard, provides gobs of low 
end torque, is probably cheaper to purchase and maintain, can be fixed by 
any decent marine mechanic, and will be cheaper to replace than a supercharged
motor when it eventually wears out.

On the other hand, Trailer Boats seemed to like the front steering fin, said 
it noticeably improved steering and handling.  The boat also has some fairly
sophosticated electronics, including a keyless ignition system with burglar 
alarm, and twin microprocessors to monitor engine functions and sound an
alarm if temp or oil pressure are on the fritz.  Then there's the "exactimer"
which automatically calculates the exact time between buoys, and sounds an
audio alert at each course buoy to inform the driver whether to speed up or
slow down for proper speed during a slalom pass.  

All of this leading edge stuff is neat, but pretty much limits the ability
of the average guy to troubleshoot and repair his own boat.  It also limits
you to having the boat repaired only by a Centurion dealer.  Is the tradeoff
worth it?  I dunno...

Rick

    The supercharger is probably a Paxton which Ford has used as a factory
    option every once in awhile for years (first time in 1957?).  They are
    relatively simple and trouble free.  The advantage of a supercharger is
    that you can have a lower compression engine which to me would equate
    to a longer engine life.  Also, I would think that high altitude
    operation would be enhanced.
    Wayne

re: .3

The only Ford production or "FACTORY" installations of Paxton superchargers 
were on the 1957 cars with 312 V8's, and the V6 in the current Thunderbird SC.
Any others that you've seen, such as Shelby Mustangs, were aftermarket options
or conversions.  

That doesn't really change the fact that even the factory versions of any
engine, whether supercharged or turbocharged, can *generally* expect a 
shorter lifespan, and higher repair or replacement costs.  Turbochargers
and superchargers increase cylinder temperature and pressure, which will
increase engine wear.  When used to boost performance, they also *encourage*
full throttle acceleration and wide open runs.  Why? Because it's so much
FUN!  

There's also quite a difference between the automotive and marine use of 
superchargers and turbochargers.  Generally, cars may see a short burst
of acceleration or high speed during which the cylinder temps and pressures
skyrocket.  Then, after the initial rush, the driver backs off to a more
sane and stable speed, which requires very little horsepower to move the
car.  Pushing a boat is like constantly driving a car up a steep hill, or
accelerating briskly from a stoplight. The engine *never* gets a chance to
coast, and is always working hard.  A turbo/super charged marine engine 
will always be under boost conditions, with the higher cylinder temps and
pressures that follow.  And this drastically increases engine wear.  In 
the case of the Centurion, an engine that was designed to produce 250 hp
in automotive use, and is now producing 400 hp under the high load conditions
of marine use, engine life is definitely going to be shortened.  Probably
significantly.

That's not to say that turbos and superchargers have no place in marine
use.  People that buy them should just be aware that repair and fuel costs
(they generally require premium) will be higher, and engine life will be 
shorter.  That's why, for most high performance marine applications, the
answer is more *cubic inches*.  Big engines can be made to produce lots of 
HP and torque on lower grade fuels and at lower rpm, reducing expenses and 
extending engine life.  That's why I suggested the Chevy 454 might be a 
better solution.  I'm sure the supercharged 351 is a kick to drive, but 
definitely more expensive in the long run.

Rick

    I just don't have enough room in my 15 footer for a 454 unless I
    removed the front seat and sat on the engine housing.  As it is, the
    front pulley of my small block Ford has scored a small mark in the
    plywood of the back of my front seat and I only have about three inches
    of prop shaft left after I shortened it for the 2.5 inch longer Warner
    Velvet drive I installed.  That's why I was interested in the idea of
    a supercharged 351.  It would "bolt right in".  Right.
    Wayne

Wayne,
Hmmmm, interesting concept - a supercharged 351 in a 15' wooden Century. 
It'd cost thou$ands to do of course, and unfortunately would *not* be a 
bolt in swap, especially if you've already got clearance problems.

The supercharger itself would probably require an oversize set of drive
pulleys, making your front clearance problem worse.  And the 351 is about
2 or 3 inches wider than the 260/289/302, due to the taller deck height 
of the 351 block.  And finally, I think we discussed this before and you 
told me that your motor has the pre-1965 5 bolt bellhousing.  Post-1965
Ford small blocks have 6 bolts to secure the bellhousing to the block.  

If your's has, or you can find a 6 bolt bellhousing, what *would* be a
bolt in swap would be a 302 H.O. from a late model Mustang GT.  It would
nearly double your horsepower and make that little "Sweet 15" fly!

Rick

    
    How fast do you guys need to go to foot?
    
    Don't the 285's from Indmar and PCM run 45-47 mph down there?
    
    Fuel injection will probably be the best thing to come for
    inboards. If you can find the premium fuel for 'em.
    
    MC had a limited edition tested in the Water Ski Mag and it ran
    a full 3 mph faster than the version with the 285 slot. The injected
    boat had the traditional 1:1 gearing which may or may not have
    increased the top speed. They also tested a stars and stripes MC 
    that came with the 285 1:1,but I don't remember how it compared
    to the other two in top speed.
    
    I do know that the CC Nau ran over 47 with the Pro boss 285 Power plus.
    
    Matt

re: .7
>> Fuel injection will probably be the best thing to come for
>> inboards. If you can find the premium fuel for 'em.
   
With emissions standards about to imposed on the marine industry, fuel
injection is closer than you think.  One minor nit though, fuel injected
motors don't require premium fuel.  No more so than a carbureted motor
anyway.  If anything, with more even fuel distribution and better control
over the mixture provided to each cylinder, fuel injection allows *lower*
octane to be used.  Carbureted motors have fairly uneven fuel distribution,
and octane must be high enough to prevent the leanest cylinder from pinging.

The only time an injected motor may require premium, is if it's installed
on a high compression/high performance motor. But those motors would need
premium whether carbed or injected.

Perhaps you're confusing high octane with the high *detergency* fuel 
required to keep fuel injectors clean?  You can have low or medium 
octane and still have high detergency, which will keep an f.i. motor 
happy.

Rick

    A friend of mine was trying to convince me to spend *only* around $2.5K
    to let him install a Paxton supercharger onto my Indmar. (This is a guy
    who has a '69 GTO convertible, refrigerator white, with Nitrous under
    the hood)  I explained to him the money would be better spent in boat
    gas, although it was an interesting concept.  I also had to give him
    some education on the requirements of smooooth acceleration in a
    skiboat, after he wanted to replace the cam and springs in the Holley
    with more "performance" (says he) oriented parts (and other bolt on/in
    stuff).  
    
    Matt;  The Indmar model 300SP (290 horse) in my Malibu still does 47-48
    MPH at 700 ft above sea level.  That's with about 760 hours on the
    Hobbs meter.  Best I ever did was 50 mph (speedo's calibrated) with a
    slight tailwind and a clean hull.  Then there was about 250 hrs on the
    boat.
    
    BTW, the cast iron version of the Viper V-10 engine that Indmar has
    been playing with looks interesting!  It's 8.0 liters (488cid), 300hp
    with 450 foot-lbs of torque and not much larger than a traditional
    small block.  See page 16 of the 1993 WSki Mag Boat Buyers Guide for
    more info...
    
    Doug

    I read the WSki magazine article this weekend on the new Ski Centurion,
    Tru Trac IV, I think. The performance figures for this boat with the
    blower aren't impressive. From 0-36 mph, any of the major mfg'rs have a
    tournament rated boat that will beat the SC by over a second (6 sec vs
    7 for the SC) without using a blower. The new MC 190 with the f/injected 
    351 will beat the SC by 2 seconds. Typically a motor with a blower runs
    a lower compression ratio so you could expect sluggish performance
    until you get the revs up.
    
    Top speed of the SC is 51-52 mph which is fast for an inboard but last 
    years Barefoot Nautique with a V-drive 454 would do that too and it had 
    the wake characteristics to be a ski boat. The SC doesn't have a good 
    footin' wake. 
    
    The 'new' streerable fin idea, although interesting, doesn't buy that
    much in the handling course. Again, any of the major mfg'rs can do
    similar performance without the extra gadetry.
    
    I value diversity but I don't see where the Truc Trac IV offers
    anything outstanding. If you want speed and ski-ability then an
    outboard would give you more for less money. For plain skiing you still
    can't beat a small block and a proven hull design. To me the MC
    Barefoot 200 with a 200hp outboard is a better package with respect to
    maintenance, reliabilty, simplicity, overall ski-ability, and cost.
    
    ~jeff

    I was at the Plaistow Beart Marine this weekend and got talking to Ross
    about the Tru Trac IV w/supercharger. My impression based on the
    performance figures are that the boat is a slug for all the HP it has.
    Ross was in FLA recently and they had one which was being demo'd. The
    throttle response is incredible (too much for a skier, rippin' their
    arms out) , very quick and fast. So something doesn't wash. He did say
    that the option will only be made available by special order. You won't
    find one sitting in a lot. 
    
    The other new Ski Centurion, the Wave, got good reviews. It's a 15'
    (?), mid engine inboard, but the seating arrangements are behind the
    engine, which might make it a front engine :^). It comes with a 302 Ford 
    small block. Priced in the $15K-$17K range it's suppose to be an entry 
    level offering. It's capable of pulling a skier with good tracking up to 
    deep shortline. It should be interesting to see if it catches on. I
    think the Base Ski Nautique is a better approach to breaking into the
    entry level market, or just buy used.
    
    ~jeff