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View Full Version : Streamers! Help w/shaft height & prop?



B.Mac
05-23-2001, 10:14 AM
Please advise on shaft height and correct prop type and pitch. Set up = Vector 200 Merc, Dual rack, Jack Plate, 6" S.B.,LWP,CONE,Torque tab (built in),relieved exhaust, TOW, Hot Foot. No weight in bow, 12 gal tank, batt, & trim pump in rear. Top shaft height presently even w/ pad (not split) Hearing differing opinions as to solid chopper vs cleaver.
Guessing 28-30 Chopper? I did try one 28 chopper w/ the weed cutters and had terrible hole shots (no bite /all slip) but once up, ran 60MPH @ 4000 before I backed off (unfamiliar w/ boat)I estimate WOT @85+ am learning though, so I'm really nervous (never chine walked yet).
Boat "felt" like it was running "in" rather than "over" the water. I never came out of the water and "floated over" the water like I expected this hull to do. Before buying & rigging this hull, I test drove a different hull (same hull type) w/ a 150 V-6 and it seemed to actually "fly" anything over 50MPH. The sensation of "Floating" over the surface is what I'm trying to find. I'm being told that a cleaver will lift the stern & give me what I'm looking for? What do all you streamers run??? What shaft height? Thanks for your taking the time to help this rookie! B.MAC

mxz
05-23-2001, 10:31 AM
BMAC,
I also have a Vector with an 81' 225 Merc, Setup is almost identical to yours. Also have a L&S jackplate w/4" of setback. My best prop is a 28" Mazco RE4. It spins 6300RPM at 81mph on GPS, propshaft just below the pad. Acceleration and getting on plane is great with this prop, I can even pull up a 180# slalom skier, think this is due to the extra blade. The "floating" feeling you are seeking is when the boat is up on pad. At 60mph I find that I am just getting up on the pad.When riding on the pad beware of the chine walk that will begin, you have to steer agians this, do not just try to drive through it. Keep practising driving at high speed, it took me a while to learn how to drive it wide open.
Not too sure about the different driving characteristics of a cleaver vs a chopper, I hope to try one of each early this Summer.
ps. My 13 gal. tank is in the bow of my boat. Last Summer I experimented running it with the tank in the back and did not see any speed difference, if anything the boat handles better at speed, doesn't porpoise as much while cruising and sits better when parked, not as much chance of a wash over the back by big waves.

Brent

mwarjone
05-23-2001, 10:31 AM
I would probably run a cleaver unless you are planning on a few passengers. (or running a load of hooch across state lines). A chopper will help keep the hull in flight if it is packing a fair amount of weight.

Glenn
05-23-2001, 11:23 AM
Hi Bmac. Like Brent says, you ain't going to feel that "floating" sensation until you get up on the pad. And that's right about where the chine walk starts. My Vision is simular to your boat. I have a 175 with 6 inches of setback. The lower unit is buried 4 inchs though. I run a 26 Chopper and it cavitates quite a bit too but once the nose comes down it hooks up and goes. The pad on the Vision (9 inches) is wider then yours. It'll start to lift up on the pad at around 57. I'm still learning how to drive through the walk. Choppy corrections are gradually turning into smoother ones. I was quite discouraged and scared all my passengers in the begining. Maybe stick with the 28 for now and get used to flying that boat. You really have to drive a boat like that. You'll probably need a 30 later on. Good luck and keep at it! Glenn

Jeff "Yammer"
05-23-2001, 06:35 PM
Bmac ,
Where do you run? Anyway if this at all helps ,you have to go through the time aspect of Stream'nn.When I first got my 91 V-king 2 years ago my first run was horrible!!Later things got better as that season went on.The next year is when I really enjoyed that FLY'NN feeling.I found that balence will take priority over driving skill.With my fuel tanks in the center and oil and battery on the port side this ended up balencing the hull {port to starboard} with my weight in the drivers seat.With my Seastar steering it flies like an F16 , very straight and very stable.My trim setting at max flight is neutral {propshaft is parallel to the surface of the water}.I run a CMC manual lift {5.5" SB} with the propshaft centerline 3/4" above the pad. 28" Yamaha Drag prop at 7000-7100 for 91-93 mph.
Anyway the "Force" is with you young "JEDI" .
Hope this helps.
Jeff.

B.Mac
05-24-2001, 07:21 PM
Finally found my fuel problem after trying everything else first! Aftermarket fuel bulb! Ran WOT today on third pass at 73 MPH consistantly. Did have 300Lb friend w/ me though (I wonder just how much he slowed me down?) I had ZERO chine walk w/ present set up in slight chop (Sarasota Bay) The boat flew!! About 6000 RPM @ 73 MPH..... Am I getting too cocky too soon? I have never chine walked or blew out before. First time over 60 actually & I'm likin it!!! Please let me know if Im about to learn something the hard way? I'm reluctant to run WOT w/o my 300 Lb buddy.Can somebody tell me the formula for calculating speed by ....RPM X PROP PITCH - what % slippage? HEY HEY IM Psyched!! Thanks everybody for being so helpful to this speed Rookie!! All input welcome!! B.MAC

mxz
05-24-2001, 08:09 PM
Congrats on getting it flying.
It will definately handle differently without the passenger, expect the chine walk to come on. When I run with my 275lb brother, I lose about 3-4mph, but it drives smoother, almost no chine walk. By myself it runs a little higher in the bow and chine walks. Definately take more caution when running by yourself. My slip is about 11%
Here is a link to a prop slip calc.:
http://go-fast.com/Prop_Slip_Calculator.htm
Brent.

Sleekster
05-24-2001, 11:29 PM
BMAC, when I use to fly the V-King, cough, weeze, back in the day....

One thought came to mind. When you come upon wakes and waves at speed, don't let off the throttle too quckly, besides potential engine damage, you loose control. Like on a bike, you have control when on the throttle. Keep it "set-up" and gentle slow down.

Chine walking is ok. When it starts, you'll know it. Takes a few back and forths before total loss of control. Anyone around you besides the 300 lb er to help you out -- someone w/ experience behind the wheel?

Use to call it the "Six-point hold". Had a friend go once who was bouncing around so much, he was stread out in the back, left hand holding the left side of the boat( that's one), the right hand the right side (that's two), each foot pushed up under the front seats (that's three and four) and five and six were his butt cheeks squeezing the back seat.

Glenn
05-25-2001, 07:21 AM
Congrats on flying that boat. Your g'na find that it's going to be a little tougher without your 300 lb friend for some reason. I've been told by many that if you are riding solo to put a little weight in the passenger seat. I sort of had the same experience as you last year. I really hadn't quite got the hang of it yet. Decided to take a 300 lb friend of mine for a ride. Warned him that it might get a little hairy. Much to my surpise, Holly Cow, I can drive the boat! It ran 5 mph slower but I could fly it, well, sort of. I don't know exactly why this is but I'm sure there are some knowlegable Hydrostream pilots hear who could tell you why. Glenn

Jeff "Yammer"
05-25-2001, 09:15 PM
Bmac ,
Congrats on a good ride!!
My opinion about the weight issue is that the more weight you add the slower you will go ..... Use the existing weight you already have in the hull..Oil tank ,trim pump ,battery etc..etc!! Do not add any weight to your hull if you can spend a little time and re-rig the stuff you already have.
That way you can have a couple O-beers as you work.
When I re-balenced my hull I went so far as to block the boat off the trailer set the boat onto two 2x4x10' long nailed together .Set the boat on the wood laying down so the boat was on the pad centered on the 3" side and put 165lbs into the drivers seat and placed the equipment in the hull untill it would not shift the hull port-starboard. It was balenced!!!!!!! The boat flew with no effort at all to drive!!......Now when someone wants to go for a ride the boat drives a little tricky!!!! there is too much weight on the passenger side!!
Anyway good luck keep at it THERE'S NOTHING LIKE A PERFECT FLY'NN STREAM!!!!!!
Jeff.

Sleekster
05-25-2001, 11:41 PM
Now that is smart. i spent more time in the V-King alone than I did w/ passengers. Makes a ton of sense to do it his way. Worth the work, I'm sure. The thrill is why you got the boat, I'm sure. Seat time, seat time....