Conference vicki::boats

re                      <<< Note 652.0 by GIDDAY::BOWMAN >>>
>                              -< shifting props >-

	from one reg to another, etc.

	I have all the guff from the folks up in NH that make 'em,  
Land and Sea, some such name.  Contact me off-line and I'll see what I 
can send - better NOT use dec internal mail, right ?

	Reg	{original}

    Whats the story, are they good or bad?

    If anyone would like to learn more about Land and Sea's T-Shift prop,
    please feel free to give me a call at DTN 285-2659. I've been following
    their development (right down the road from me in Salem NH) for the
    last few years.
    
    The bottom line is - yes they do work, BUT you must tune the
    pitch/blade type and range of change for each specific boat. Oh yes one
    more thing, after each season of use the prop should come off and all
    moving parts should be checked for wear and pitch stop slipage.
    
    Give me a call, and I'll get into more detail.
    
    BTW - I've seen 80 + MPH Hydrostreams (HST model) stand right up on
    it's tail on hard acceleration with this prop.
    
    								-mike-

re .2

	Well, according to the literature they gave me - they're  VERY 
GOOD ! (-:, (-:

	I dropped in at their place in Salem NH  last year
( I might have been on the way to somewhere like Rochester ?)
and had the guy bend my ear for an hour or so, interesting stuff.
As Mike will probably confirm, they've changed the design quite a bit
in the last year. I think there are now four basic hubs, Merc & OMC, 3
& 4 blades.  They make a big deal about being able to swap the blades
around between a 3 blade hub and a 4 blade hub - just buy the 4 blade
hub and another blade, right ?     WRONG !  they neglect to remind you
that for any given boat you'll need substantially smaller blades when
going from a 3 to a 4 blade set up - I'm pretty sure you can't make it
all up by changing the pitch stop(s). 

	About $500 for a 3 blade set-up  -  but they'll convince you 
that its worth more than 2 stainless props....

	Reg

    
      There was just a test in one of the boating mags, (I forget which,
    but I'll look it up). They really liked the prop, but DID say that
    the prop HAS to be tuned to the boat. Apparently, it is only available
    in larger sizes right now (probably has to do with the size of the
    hub), but it sounds like once it is set up correctly, it doesn't
    need much maint(I got the idea that it used to require more
    maint). If they made a V4 size, it would probably get my interest.

    					Kenny

    well they told me the smaller size was a few months 
    away.
    over here their about $1000 so im checking up before 
    i buy 
    im really curious about the different tuning for the 
    different boats id be only using it for social ski really 
    so im thinking of a laser cut 
    ill read back through all the replies again thanks for 
    your advice
    thanks reg
    

	I had the opportunity to try one (finally) last fall.  My friend bought
one for his 5.7L OMC-cobra and oddly enough, that the same engine I have.  I
have a 20' EuroSport II (Sunbird) with a 42gal gas tank, so I figure my "wet"
weight is approaching 4-4.5K.  I currently have a selection of 17" and 19"
stock OMC aluminum "rock-finders" (props) that either work well for skiing
(17") or for crusing (19").  Top speed with the 19" is about 50-54mph
depending on the wind direction!  The 19" is "doggie" pulling a skier out of
the hole, but the 17" reduces my TOP END by several mph, therefore I am
really interested when someone advertizes that I can have both ends, so...

	At first the prop (as adjusted for his boat) did not perform well, but
then his rig is  800-1K lbs lighter.  After about 3 hours and 12 different
attempts at adjustment, my rig literally LEAPED onto plane!  Adjusting the
prop is really half the fun, as I could have spend another 3 hours tuning
it better.  The prop "shifting" points can be controlled by your TRIM angle,
simular to manually shifting an automatic transmission.  In_other_words
if you don't want it to shift "UP" as quick, keep the motor trimmed down.
If you don't want it to shift "DOWN" as quick, keep the motor trimmed up.  If
you want it to shift per the natural torque patterns, keep your motor trimmed
level.

	IF I had $500. sitting around I would buy one in a second!  However,
this prop is not for the poeple that buy a boat, put gas in it, and use their
charge cards for all adjustments/service.  It does require understanding of
propeller forces and mechnical principles in order to get the adjustments
correct, but it is not rocket science.

	If you have a very HEAVY boat (like mine), or are slightly
underpowered, or like both good TOP END and great SKIING pull, this prop's for
you.  I would suspect (however) that if you hit a rock (or something else as
solid) you might damage more than just a blade.  L&S claim that the blades will
take the force and sheer off, but last time I checked Stanless Steel is pretty
strong stuff in its own right.  If you boat in strictly deep waters (Winni,
Sebago, ocean, ...) or you REALLY know your swimming hole', its a good bet.
After 20 years of boating without losing a prop, I "consumed" 2 last year,
so I am not in any hurry to move to Stanless right now, let alone $500 worth
of it.

	Trailer Boat mag. did a test a few months ago and also liked it.  What
else can I say...

	Cheers,

	Garry

    okay one more question 
    ive been discussing the props with a mate across the road
    and he was curious as to wether anyone had raced two up
    with one 
    hes running a 15 foot bullet tunnel deck (mono)
    with 175 2litre merc 
    and wants to know if these are suitable
    tks reg
    

    
      From what I've been reading (and using some common sense) the
    Torque Shift props will NOT increase your top end speed. Their virtue
    is they give good acceleration AND then shift to provide a good
    top end. 
    
    					Kenny

    .9
    
    That's correct Kenny, the Torque Shift Prop will not give you  a
    greater top speed then a similar pitch SS prop. Land & Sea has worked
    very hard over the past few years designing their prop so they would
    not loose any (or very little) top end speed. This along with
    reliability, was one of their top priorities...
    
    								-mike-

    the other reg again
    
    as ill be using my prop prop for social skiing the torque
    shift sounds as if its perfect for me.
    however my mate who races (usually two skiers on back)
    has a few reservations.
    although it would be great for the takeoff once up he would
    be in dire straights if it decided to downshift on him at speeed
    whilst doing the bridge to bridge or any of the other races
    also he doesnt want to loose top end or very little top end
    
    just for interest the bridge to bridge boat race is on,on the 6th
    may this race is over 100ks (i forget the actual distance)
    there are two races one only boats the other with skiers
    
    the best one is when they ski race bridge to bridge and you get
    some suicidal skiers hanging on at 100 mph.
    this is quite an event over here amongst the skiing fraternity 
    
    tks reg
    
    

To revisit this topic, I have a couple of questions. First, how abrupt 
is the shift, ie: if you a bare footing and it decided it was time to 
shift would the skier notice it? 

Second, aren't there some models available now that provide a gradual 
shift thru the pitch range? 

And lastly, since I have an inboard, are there any manufacturers that 
props for these shafts?

Thanks,

Steve

    Steve, trailer Boats Mag, over the last couple of editions, has been
    comparing all the different brands and types of props available
    including shifting props.  I am not in my office right now or I would
    tell you which month covered the three or so different brand of props.
    
    As far as I know, nobody offers a shifting prop for an inboard.  I have
    an inboard so I would have noticed.  B + M tranny does offer a two
    speed reverse gear.  Just came out this year.  I haven't seen a
    write-up on it nor do I know the cost.  It supposedly is a direct
    replacement sizewise for a Warner Velvet Drive which you probably have.
    Wayne