First of all, you are best kept secret for Hydrostream Tech. I really
appreciate what you are doing here and regularly stop in to see if I might
find some Vulture tech:)
Well it seems scarce, so I just better step-in and ask!
We have been fortunate to find, what I think is going to be a good solid
project boat. Aside from some gel fade and the need of a good
cleaning...we have found an all original 1980 "CocoLoco"
Vulture. The Boat has been recently moisture metered and it is not near
needing a core, transom or floor replacement ...Lucky me cause this needs
to be a budget project. This boat was meticulously owned by the original
owner for 20 years!!
Knowing full well that the Vulture is probably the toughest Stream to
set-up, am looking to just put together a modest 75-80 mph
ride...that is efficient and well set-up!
So plans include setback and, of course, a good prop and gearcase.
Here are my questions
I certainly want to play with the Center of Gravity (C/G). It is my hope
that maybe setting the front seats back 6 - 8" might help. This
Vulture has back to back, high-backs....Are the seat bases removable or
are they glassed to the floor? If they are glassed, is there any
effective way of placing them farther back without cutting the boat?
I am considering the use of a Merc Paralift for setback. Do you think the
standard transom will be structurally adequate with say a 400# Merc fixed
to it and the Paralift? Should I do some transom reinforcing like
Knee braces? If I have the 20 gal gas tank, is there any room to make some
small knee braces? If the transom and the floor are good, will glassing
these knees braces from the transom to the floor, be adequate or do you
recommend getting in the stringers!!!
Since the Vulture requires setback and lift, here is what I am thinking. I
would like to use a Sportmaster (SM) gearcase due to their good stern
lifting qualities, but knowing full well that it only works well with 0 to
+/-.5° neg trim. So this would mean my hull has to be flat, sharp and
aerated. Does the Vulture have a factory hook or flat pad? If is has a
hook it will be hard to drive the SM the way it should. Should I flatten
the pad? What do those speed rails on the Vulture bottom really do???
My hope is not to waste too much energy trying to lift the nose of this
Vulture. So I am hoping to use the SM's stern lifting qualities to fly the
boat flatter and hopefully more efficient. What do you think?
I plan to power this set-up with a 200 something carbed Merc. What have
you got you can build for a guy on a budget with an SM case and maybe an
I really like Merc ETs and the new Chopper IIs...what do you think?
Again I am hopefully not going to bury the transom of this boat just to
lever the bow.
Aside from this, the boat will undergo rewiring, switch to opposed
steering and some gauge cleanup...drive-it and go have fun, for our
young family of five, and some grandparents. It should be a sweet boat to
do that in, and some fun for dad too.
THANKS...I anxiously await your thoughts and again, I appreciate your
The photos of the boat look really good. Getting the
Vulture to run 75 to 80 is actually quite easy. In my opinion, do not, I
repeat DO NOT, run the paralift on the transom on that boat. Several
things will happen:
1. Those little aluminum wings
try to correct the water flow coming off of the center pod. The farther
away the gearcase is, the nastier the water to the gearcase. This is an
unusual phenomenom, but we worked on one this summer that had me stumped
until I moved the motor to a 6 inch jackplate from the 10 inch one that
the boat had on it. Believe it or not, we gained bowlift by shortening the
2. The transom on that boat was
not intended for any jackplate, so you can imagine what a paralift would
do to it.
3. With those little aluminum
wings, and the long pod-like pad, the boat actually has a lot of natural
taillift and does not like to be flown with it's nose in the air. We ran a
noseconed Bob's case at an inch or so below the bottom. Had gobs of
bowlift, and easily ran 80+ with a 200 ProMax.
4. Moving the seats back would
probably help. Tork, who works with me, had a Vulture that we took to Balz
to the Wall Fest 1, and we moved the seats back 5 inches. Now this boat
had the bucket seats in it, and not the highbacks like yours. Those
highbacks, as you know, weigh a ton. So, I would exchange them for the
newer style buckets. The seatbox is glassed in, but you can remove it with
a cutting wheel on die-grinder. You cut around the outside edge and lift.
We ran a 6 inch steering extension to a formuling wheel and it worked
great. To gain some of our seating back, we moved the backseat a foot
forward and built a little deck behind it. Now we gained a ton of fuel
tank area, and were able to mount the battery right in the center.
5. Make sure the hull pad is very
flat. If it is not, blueprint it. Also remove any hooks from the tail on
the outside of the pad going up towards the lifting strakes. Some of the
boats had these hooks put in. If you remove them, you won't believe the
difference. Because of the height you need to run the gearcase, the
Sportmaster would actually lift the bow, not create taillift. Running the
gearcase at or above the bottom, would not have
much benefit in this particular case. Until we break 100, there is no
reason to have the gearcase that high.
6. On Tork's boat, we ran 2 inch
spacers behind a Land and Sea jack for a total of 6 1/4" of setback.
We ran the jackplate down a couple of inches from the normal height of 1
inch below the bottom, only when he carried a larger person in the front
with him. And even then, the boat would still run in the high 80's.
Granted, this was with 260 ponies.
I hope this gives you some food for thought, and I
could share more detail with you if you wish. We ran our Vulture for 2
years, and tried a lot of different things in it and started with 200
stock hp. The boat would run over 80 with the 200, so I think it would be
what you want. As far as building a motor with or without an offshore
center, that is kind of what we do, and I would be happy to discuss any
combination with you. You can
contact me through our website, www.gpiracing.com,
or you can give me a call at (320)267-0440 (cell) or (320)356-9068. I
would be glad to talk about your project anytime, so feel free.
whatever questions you have to IHRTechTalk@yahoo.com.
All questions and answers selected will be displayed on this page as they
come in. Note: though all boaters are welcome, priority may be given to
members. Randy can not be held responsible for any advice
given. Though his information and expertise is second to none, he
has no control over what you do with your boat. It is up to you to
boat safely and act responsibly, and his advice is only to be used as a
guidance for your high performance boat/motor of which you are the one
responsible for the risks involved.