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Ventura I
03-01-2005, 11:47 AM
Hi all,

I'm setting up a Ventura I (20" transom), with a 77 inline 150 (20"). Last year with a 21 aluminum 2 blade (propshaft about 7" blow the pad) it ran 55 gps @ 6200 rpm. Since then I've added a manual jackplate (2 1/2" setback), tilt/trim and I have a 26 Laser II.

I've read alot on this site about the Ventura and the FS class. What setup was used? Any idea how high the inline can run with a stock lower unit (no low water pickup), right now I have the propshaft 3" below the pad. What prop was used and the true speed they would run. I think I read where the min. weight was 1450#, I should be about that weight with 2 people. How fast can I get thing to go.

Any info would be great. This is a great site and the Ventura is a fun boat at 55, can't wait to go faster. Although my wife thinks the boat is the ugliest thing on the water, (a little faded gold metal flake) my boys and I like it, they have named it the "Flying Booger" , the color is right, need to work on the flying part now.

Thanks,
Fred

Raceman
03-01-2005, 12:30 PM
Fred, those motors will run a lot higher than you think. We use to plug the top 2 holes, but I ran mine (15 Allison) for a long time without even doing that before somebody suggested it. When you look at em it's hard to figure how they got water at all. My guess is you'll need to be up within an inch of the bottom of the boat with the propshaft. Those were raced mostly before the cleavers and choppers were used and most people ran round ears. I'd try both a cleaver and chopper on it and see which you like best. The chopper of course will give more bow lift.

Back to the water issue, the Stream will actually be better than the Ally since it's got a notch at the back and the pad of the Ally went all the way to the back of the boat. The setback plate will help the water problem for the same reason, although I don't know whether the boat really needs it except to optimize transom height. In the mid 70's nobody was runnin' setback plates on em. In any case you need to put a water pressure guage on it and watch it. Inline 6's don't have a lot of tolerance for cooling deficiency.

My memory is a little foggy on the class designations but I'm pretty sure the F classes ran 4 cyl engines. The 1500 V bottom with driver only was JP (J production) and JS (J Sport) for tunnels with 1500's. I can't recall what they called the class that was basically JP with a passenger, but I've got it in a book at home.

Ventura I
03-01-2005, 01:12 PM
Raceman, I was thinking FS was family ski, and they ran inline 6's, I could be wrong though. I've got the water pressure gage, does'nt seem to get alot of pressure though, even with a new pump. The pressure line is tee'd at the block with the pee line, does'nt seem like the right place to read pressure tied in with a open line, not sure how it could build much pressure, I get about 3 psi @ idle 7 or so @ 6,000. Whats the best place to take the water pressure and what's good pressure. Plug top two inlet holes with marine tex? Thanks

Dukeofchippewa
03-01-2005, 01:28 PM
Yes, FS was Family ski, with one passengers.

Hydrovector
03-01-2005, 01:51 PM
FS class rules were prop shaft had to be 5" below the bottom of the boat. I have a buddy in Ohio that still has his Ventura that he races in FS. It was set up with left side driver. I rode in the classs with him a couple of time when he was racing. I seen to remember the boat doing 70's or better. He has a 150XS on it. He got it from Howard with the transom cut down for the short shaft engine. I'll have to check with him on top speed if your interested.

Mike

Ventura I
03-01-2005, 02:05 PM
Mike,

Hey, I'm in Cincinnati, someone else in Ohio with a Ventura, thought I might be the only one. Yea, if he has the time, I'm here to learn. By the way how is the ride on a Ventura at 70+. Thanks

Hydrovector
03-01-2005, 04:39 PM
Well I was a young in the 70's, Racing my Vixen was great. getting in his boat back then scared the hell out of me... I wasn't used to it being bounce around in the passenger seat. Was great though after getting used to it. my buddy is in Cuyahoga Falls and makes trips down to Salt Fork State Park a couple of times a year. Maybe you could meet him there someday.
There are a few Venturas floating around in Ohio. I know of one that has been sitting in a guys back yard that hasn't been uncovered for 15 years.

I just noticed your in Loveland. I used to go down there for work. A pattern shop, the name escapes me.

Jimbo
03-01-2005, 05:06 PM
The FS class or "family ski" was started in 1973 and the first full year of racing was in 1974. The kilo record was set by the owner of Hydrostream, Howard Pipkorn in 1975 at 74.3 MPH. He did it with a Ventura hull and a 1500 (150HP) short shaft Merc.

The class ran with a driver and one pasenger. The minimum weight was 1450 Lbs. ( including fuel and pasengers when lifted from the water). The prop shaft had to be 5 inches below the boat botom. This motor height simulated the height at which it was thought was the maximum height that could still pull a skier.

Hope this helps.

Jim

Raceman
03-01-2005, 06:00 PM
Y'all boys are right. I was confusin' the FS with the GP class which was the 4 cyl V's. I said it was foggy in my mind, and I wuz right about that part anyhow.:o


I don't recon' I knew anything about the 5" below the bottom of the boat rule though. Seems like that would've made the 74 MPH kilo a real challenge.

transomstand
03-01-2005, 06:53 PM
Hi all,

How fast can I get thing to go.

and the Ventura is a fun boat at 55, can't wait to go faster. , need to work on the flying part now.

Thanks,
Fred
Ok Fred,
What happened to all this talk about watersports and tubing, eh? :D Seems like you got bit by the bug. If I knew in 1976 that I'd be sitting here on the internet, talking about a 30 year old setup I had, I'd have wrote some stuff down! I'd probably also be filthy rich.
I would have to think you've got a 65-67 mph boat right now. I'd move the engine an inch higher without any concern for water pressure loss.
What I don't like is the current readings your getting. They seem a bit low, but I can't remember what my readings were back then. From what you described, I think your fitting is in the correct location, a tee in the center of the water jacket cover. That sounds like the same set up I had. Might be a good idea to investigate that some more.

Pete

Jimbo
03-01-2005, 08:21 PM
Answering some of your questions.

That Ventura will give you a smooth ride at 70+ MPH. Just be carefull you don't over trim and get too much air under the bow, they will blow over if you get careless.

With your motor at three inches below the pad and the 26 lazer you should be in the 65 to 68 MPH range. From there you can continue to raise your motor and experiment with props. An old style Merc chopper made for those inline Mercs should work --- try to find a 14X26 prop. A trick to maintain water pressure when raising your motor --- block off the top two or three inlet holes in your gearcase ( this prevents sucking air into your water pump). You can do this by drilling and tappng the holes and screwing in some set screws --- this allows you to remove them later if you sell the motor or change your mind.

I had a Hydrostream Vector in the 1980's with a 140 Evinrude with nose cone and reworked water pickup. I could run a consistant 72-73 MPH and on a good day I could run 75 MPH.

Hope this helps.

Jim

Ventura I
03-02-2005, 09:54 AM
Pete, yea forgot all about pulling anything behind the boat, it's just fun to drive. Actually we have an inboard comp. boat for that sort of thing. I don't like that low of water pressure either, it's been like that even with the motor all the way down, it's time to check out the pump even thought it was new when I got the motor. As soon as we get weather in the 50's I'm going to see how it runs, I'll let you know. Thanks

Fred

Ventura I
03-02-2005, 10:02 AM
Jim, thanks for the reply, so if it's possible to get into the low 70's with the propshaft 5" below the pad, any rule of thumb 1" up=? mph. I was thinking the Laser II was very similar to the inline choppers (except has the through hub), would a chopper be that much faster?
Fred

Ventura I
03-02-2005, 10:23 AM
Mike, know what you mean, I had a friend that had a 18' Baja that had a 400 hp small block. Thought we were going to blow over every time I went out in that thing, I feel much better when I'm behind the wheel. I hope to get out and try the setup soon. I'll post what happened.

Fred

Jimbo
03-02-2005, 01:22 PM
Ventura 1

Yes it is possible to get in the 70's at 5 inches bellow; but remember Howard Pipkorn who set the 74 MPH record knew how to drive and set up his own Hydrosteam boats.

It is not possible to rely on a rule of thumb when setting prop shaft height. Every boat design and setup has different efficiencies. One rule however that will help to keep in mind; when the boat is running at full speed, the prop shaft should be parrallel to the surface plane of the water. This is the so called sweet spot where the combination of motor height, motor setback from transom, trim angle of motor, prop design and pitch, and the overall weight balance of the boat come together to allow the hull to ride efficiently with the prop shaft parallel to the water surface. Reaching this point is where all the hard work and experimenting pays off. By having the prop shaft level, all the horsepower of the motor is pushing the boat forward and not wasting power trying to lift the bow.

The laser is a good prop design. However, it never hurts to experiment with other props, sometimes your surprised by the results.

Hope this helps.

Jim

Ventura I
03-02-2005, 02:15 PM
Jim, kinda what I thought (try it). I'm going to start at 3" below the pad, and see how it runs. I will plug the top 2 inlet holes. Thanks for all the advice.
Fred