PDA

View Full Version : Hydrostream Vector setup/handling



scanman
05-14-2001, 01:27 PM
I've an '87 Vector, Mariner 150 with nose cone, LWP, torque tab, CMC powerlift and run 26" chopper and Lazer II. Boat wants to porpoise at most speeds unless in the "sweet spot" of throttle, trim and lift. Also chine walk at 55+ is pretty hairy. Any setup ideas to smooth out the ride ? Jack plate has 5.5" setback, prop shaft runs at pad height in highest setting. Would tabs or less etback help ? Thanx in advance

AnthonySS
05-14-2001, 02:30 PM
WOW, Vector tech has been real popular lately,

If that is a prop rated 150, you have the potential for an 80+ Vector. However you won’t get there that easy with a 26” chopper / lazer.

If you have 2:1 gear ratio, you should be able to spin a 30” wheel at 6-6200 rpm even with a stock 150. However my choice prop would be a cleaver style on a hull like yours that does not need the bow lifting characteristics of a Lazer or chopper.

I really like cleavers on sub 18’ Streams. This is due to the Cleavers low rake design (except 32 Cleaver). This is the angle, perpendicular to the hub, that the blade sweeps back, when looking at it straight on from the side. This angle is generally 12-15° on low rake cleavers. The low rake enhances acceleration and helps lift the stern giving your Stream a non-kiting (more friendly) effect on the bow and a more stable angle of attack into the wind.

These sub 18’ really do not need the bow lift of hi rake round ear props like choppers. Also steering torque will be less with a low rake and the boat will be easier to drive on your own. Big Blade choppers tend to make the boat roll over on its side and it is probably not helping your chine walk.

The chine Walk will go away with more seat time. By raising the motor you will shorten the axis, the boat has to rock over on. In other words, the distance from the bottom of the pad to prop shaft c/l will shorten up. Also, make sure the steering is adjusted to have very little play. This will assist with chopping the steering when the boat wants to start walking. Your prop shaft centerline even with the pad should be a good optimum setting.

Chopping the steering means, literally that…take quick short strokes back and forth on the wheel turning the wheel opposite to the direction of the rock. It really works and gives you a work-out to boot.

The porposing may never go away as it is function of a short boat, with setback, a 400 lb outboard hanging off the back and a flat pad. These types of boats will usually have no midrange cruising speeds. They just have dead nuts slo and WOT. I am not sure if the Vector had a hook from the factory, because a hook in the pad will reduce porpoise but could scrub top speed.

The new Lighting ET can also be designed with low Rake. It has even less rake (10°) than my cleaver and therefore accelerates like a “scalded cat”. I would recommend trying one of these, if you can find someone to loan you one. However, it is NOT a budget prop. Try a 28 –30” pitch would be in order for trial.

It takes RPM and Pitch to make speed! You will not get good results until everything is optimized and mechanically fit to the max. to get top RPM and make top speed

I have seen guys get all the right stuff but have scrimped on things like mounts and steering. You will not be able to drive the boat to the max if you cannot first tame it with the aid of Solids and good steering. This also assumes you have a F/T and remote trim so you can have two hands on the wheel at all times

Optimizing your setup means you have get that motor running as perpendicular to the water as possible. Again, this is were the mounts steering, and, now, a torque tamer comes to your rescue!

Don’t Forget Safety….

First, before you go fast, make sure you have all the go-fast SAFETY Items are in check.

Foot throttle, Remote Trim (on wheel or floor), Dual Steering, Kill Switch, Solid Mounts a good hi-Impact life vest and wear a Helmut and restraint when doing hi-speed runs! Make sure all mechanical items are secure and fasteners are tight.

When performing setup and prop swaps, leave all buddies, girlfriends, wives, kids, mother-in-laws and pets on-shore. If you want to scare someone out of supporting your go-fast ride, this is the time it will happen, when you are trying to learn how to drive it! Furthermore, it is always good to have a buddy-boat or someone onshore spotting you in case you “go for a swim”.

I hope this Helps Some,

Sincerely,

AnthonySS

84exciter
05-14-2001, 03:37 PM
scanman,
i'm an ex-viper owner and i'll let you know what i learned.when i bought the boat it had a '83 140 'rude,run great about 58-60 with a 24"prop.the worst thing,a lot of porpoise and chine walk.i found a '84 2.6 GT johnny,added a cmc jack and a 28 pitch large ear merc. chopper.adjusted the steering and took it out.95mph at 6700 on gps (no limiters)smooth as silk to drive(but watch the wind,the viper can blow over above 80)i never did but got close a couple of times.I've got some pic if you want to see her at 95.

Raceman
05-15-2001, 03:23 PM
I have to disagree with the above post that the Vector's hook will reduce porpoise but may scrub top end speed. The factory hook in the Vector was designed to lift the rear of the boat, unwetting the bottom without a bow high running angle. The high angle of attack on the hooked portion of the pad allowed the rest of the boat to run flatter, reducing the aerodynamic drag. This allowed the Viper, Vector, and early Ventura to be extremely fast by comparison with other boats. I know of 4 Vectors that had the hooks removed back when I was selling them, and in all cases the boat lost top end and the owners were dissatisfied with the overall result. The Viking, which has a flat pad runs slower, higher, and porpoises less than the Vector. It is a better ride for recreational use. Vector/Viper-racehorse, Viking-pleasure horse. HydroStream offered some trim tabs for the Vectors in the 70's that were essentially aluminum angle, to be bolted in an exact location. HydroStream claimed no speed loss if they were installed in exactly the proper location. They did somewhat enhance the low speed and mid range manners of the boats but I never liked the feel. They somewhat removed the boat and made it feel somewhat "pinched" to me. I've also always felt that the Vectors did like some bow lift to push the boat against the hook. While cleavers are primarily stern lift blades, the hook does a pretty good job of lifting the stern on it's own. I've seen people run both types satisfactorily, depending on the rest of the set up. One other thing I never did overcome with the Vectors was feeling comfortable with the boat really aired out and sitting in a right seat with no passenger. The center steers were a breeze to drive, but I used to sit between the seats and drive from that position when alone in a side steer boat.

Raceman
05-16-2001, 06:45 AM
Mark, my ideas of how the Vector's bottom work are based on my experience with the boats as well as with the Allisons which we built much smaller hooks on. When Paul Allison (Darus' father) sketched me his detail on hooking my Allison pad years ago, his explanation was basically what I always came to believe as the reason the hooks do what they do. When I was having handling problems with the Allison later, he said that the way we built it combined with the speed the boat was running was literally lifting the boat off the water. I've always considered them a reverse spoiler providing lift as opposed to downforce. I've seen numerous Vectors ruined with the pads straightened. By ruined, I mean loss of top end. I will say this for sure. The fast ones at the races always had the pads and there were at least 4 boats here that were disposed of after pad removal. I'd also have to add that while there may be a number of fast Vikings in the speed range you mentioned, I believe that in all cases a Vector is faster with equal power and setup, although the Viking is definately easier to drive. Although I remember seeing a comp Viking or maybe 2, I don't recall that they were ever competitive. You bring up another interesting point. There've been several comments on the boards (many from Sam) giving Ron credit for the design of the Vector bottoms. I've never talked to Ron and don't know him, but being an absolute HydroStream fanatic back in the early days of the design, I never heard any of that before. At that time Pipkorn was thought of as being the master of the design and I did have occasion to talk to him on several occasions. If the design was somebody else's, he wasn't sharing the credit back then. Sam made several comments on somebody else's post on the old board about bottom design which made it clear that he and I have differnt ideas about what goes on with the bottom of a pad that's not straight. In this particular case the issues of lift and aeration seemed to become confused. I've always believed the hook is for lift. Another reason for this was the fact that we had to always lower the transom slightly with the hooks. This seemed to indicate that the boat was running slightly higher. Incidentally, no need to apologize for posting a different opinion. I know that you've got a lot of HydroStream experience under your belt too. Hope you don't find mine offensive either.

Rickracer
05-16-2001, 07:42 AM
I believe your idea about the hook has much merit, but it may boil down to the individual hull as to whether or not the hook has that much effect. I did a bottom blueprint on a boat a few years ago, but due to a broken crossmember on the trailer, it developed a worse hook than it started out with. I plan to flatten the pad on my 1st Vector, but may put a slight hook at the transom, just to see if it helps with lift. I can't argue with 80 mph out of a flatpad Vector with a Xflow 135 on it. It does tend to porpoise a lot when it isn't near wide open, but I can live with that.

Instigator
05-16-2001, 08:03 AM
I just bought a rig almost identical to yours. '77 hull, '89 150 Merc (2:1 gears) stock gear case on a mech. jack plate.
Basically I agree with almost everything said so far. I've only ran my boat one time and my experience started similar to yours. I have experience in driving pad bottom boats that like to chine walk. The mistake I made in learning to drive this boat was that I was over correcting (the steering chops) and make a bad situation scary as ****!
Once I realized this, and I reduced my steering imput the boat drove like a dream!
Funny thing too, no problem with porposing, my boat had the tabs that Race Man was mentioning (you want em?), but the mounting location is far enough out on the hull that I can't see them doing anything above about 20 MPH.
My prop shaft is about 4" bellow the pad and I turned a 29" SRX 6-6200 RPM's for 73-75 GPS.
Raceman, I agree with your scenario on the hook/pad as well. It took me a while to get past the urge to grind it out, but I believe it does work! I also think at warp speed it's not really a hook anymore. I believe the small amount of pad thats still in the water is at a different angle than the rest of the bottom, but I don't think there's enough in the water to still act as a hook.
I also believe that with the concave shape of the pad that it forms a "seal" and pressurizes the pad lifting it out of the water at speed where the flat pad boats let this water/lift spill over the sides of the pad.
84EXCITER, can you send me picture of your Viper at speed?? I'd love to see them!
Scanman, Anthony is right too, take the slop out of the steering (if there is any) put on a vest, hook up the kill tether and go give your self a driving lesson, thats what I did. I started the day feeling like someone was holding a loaded gun to my head at speeds above 50, to feeling like I was flying the boat like no one else could!! You also make a good point about the sweet spot. A boat of that design/size/weight/power will require abjustmets to trim every time you adjust speed or to compensate for weight/water/wind conditions. Ditto for the jack plate, the higher it is, the more sensitive the boat becomes to these changes. Anthony is also right in the fact that you own an 80 MPH boat. Previous owner of mine claims low 80's with a good lower unit.
Get your seat time and remember safety first!
Good Luck,
Instiagtor

[Edited by Instigator on 05-16-2001 at 08:11 AM]

Jeff "Yammer"
05-16-2001, 04:24 PM
Well not much to say about the Vector ideas.
I have a 91 V-king that runs like a dream and a friend
that owns a Vector with a 94 200 . I helped rig his boat
so it is balenced as I would have wanted it if it was mine.
His boat is a concaved pad design When we ran last year
before I blew up my yamaha I was allways 5-8 mph feaster
than him. Is his pad suposed to be concaved as well as
hooked.
About the whole hooked pad idea. My thoughts about it are
if it was originally designed as just an angle change
to me it would affect speed but would would help planing.
If it was designed as a progressive bend then yes I think it would hinder speed. Say the hook was a designed as an angle change if you take a piece of metal 6" wide by 8'
long bend it then there you have your "Hook" but if you
cut it at the 4' mark weld it at a 3-5 degree angle up
from flat is that still considered a "Hook" , to me it
is not. If the boat at MAX-FLIGHT is only running on the
last 3-6" of hull in the water it is running on a flat
0 degree hull but at lower speeds with the entire pad in
the water, then yes it would force the bow down.

Anyway just my thought s and points!!
Great respectfull replies and thought so far!!

Hope to read the expert replies to my thought!!
THANKS
Jeff.

Instigator
05-16-2001, 08:17 PM
I have owned boats for the last 29 years but because I have only owned an almighy Stream for a couple of months I don't understand bottom design/fluid dynamics???
Vector makes my 5th pad bottom by the way.
And tell me O brilliant one, how high can I run my merc w/o a cone/low water p/u???
I give up.
Guess I gotta have one of those black motors to be one of the boys huh??
Current and reigning Scream and Fly Offshore Boat of the Month Instigator

[Edited by Instigator on 05-18-2001 at 11:00 AM]

Raceman
05-17-2001, 08:06 AM
I've been looking for the pages I got from HydroStream after one of my calls to Pipkorn but I can't seem to find them. Bear in mind this was sometime in the late 70's and even being the pack rat I am they may be gone or at least crammed in some unlikely place. As best I remember they were engineering drawings showing a lined scale of the Vector hulls similar to one of the pictures on one of the boards showing the boat almost like a skeleton. I'm shure these drawings had Howard Pipkorn's name all over them and I even think I remember a patent number in his name on the bottom. I could be wrong about that last part, but it sure seems like I remember it in some kind of printed circle almost like a seal. I guess it could've been a copywrite also, but I remember it as a patent. It also seems like there was some engineering data and seems like it described Pipkorn as a Mech. Engineer which was my major (uncompleted) also. Remember it's been almost 25 years and a lot of Skotch and water down the throat since then. I'm not for a minute saying that Mr. Baker didn't design or redesign that bottom, I've just never heard it until in the context of one of Sam's posts concerning their knowledge of bottom design. One other thing that you bring up that's unfamiliar to me is the term Vector II. My love/involvement with them started in about '76 or '77 and I quit fooling with boats after I blew the Allison over in '81. If there was a major redesign of the boat, I'd like to no more about the changes as well as the time frame.

Hank W
05-18-2001, 09:13 AM
When I got my Viper in 1976 w/a115 inline I remember the first time I trimmed her out...scared the crap out of me..trimmed it back down & waited another week to try that again. When I did it the next time, I scared everyone else in the boat. I drove the boat the next20 years with no jackplate& single cable steering, no foot throttle.. you know what that means! 65mph with never more than 1 hand on the wheel, 1 always on the throttle. I thought my experiences with this boat made me a skilled any boat pilot...WRONG.. When I test drove my GranSport to be I was sure I would know how to drive it.It of course came with dual steering & foot throttle It took me 3 weeks of driving it to get around the "walk". Somedays chopping works for me and somedays holding steady works better. There are no directions for stopping the chinewalk to me. Just use your brain and learn your abilities and your boat's curve a little at a time. I think for "rookie drivers" Jim Barnes' Allison ownwer's handbook would apply to most pad vee bottom boats though. Thanks to all the different posts above I am now thoroughly confused as to what prop I want to try next on my Viper. I don't suppose I could get everyone on this forum to send me his/her prop to try could I?

[Edited by Hank W on 05-18-2001 at 09:21 AM]

Hank W
05-18-2001, 09:20 AM
By the way,My Viper porpoise is always stopped quickly at crusing speeds by lowering the plate and tucking the motor.

84exciter
05-18-2001, 02:27 PM
i see what u mean.
i just stopped to look at a 89 viper,i saw the concave pad and the wedge(i wouldn't call it a hook,too much of a distinctive change in angle)my vector was an 83 it's pad was straight and flat,i never had any priblems w/ handling.it flew the bow very nice with a chopper.instigator&yammer saw pics at speed.i think i'll call the guy selling the viper and take it for a ride.gotta ditch the black thing on the back though.it would make a great crab trap ancor!