Reply With QuoteOh yeah, I didn't even have 500HP to play with.
Steve.
The pump, the pump, the pump, and then the hull. I just sold my Gullwing which ran a best of 82.6 mph at 5200 rpm, with an MPD-prepped A/B impeller. A 25K engine with a stock pump is like a pro-stock dragster running on dry rotted Sears radials. Tell your buddy to put some work into that JC, and possibly upgrade to a split bowl pump. Make sure it's got a ride plate, shoe, and loader, or just go out and buy a high-perf hull to put his drivetrain in. If you want to go fast, you've got to have a fast hull. Something air-trapping works well.
SteveM.
Oh yeah, I didn't even have 500HP to play with.
Steve.
Those that have been pointing you in the direction of the hull are correct. I have a Dana that is a splash of the Eliminator. It is a heavy boat, and if your friend wants to run fast, I would pick a different hull.
All that asside, I'm a little shocked at the HP to mph factor. Turning an AA at 6500, I would think he could do a bit better than 74. Especially considering that my goal is 70 on a shade over 500hp at 5200 rpm. I have had fuel system problems so I can't compare, but I would agree that the pump might want to be looked at. Someone also mentioned your wetted surface as a point of degraded performance. With that hull there is a lot of drag, and any mods that would create lift would get your friend in the right direction. The line about the JC being a cheapo version of the JG... I take exception to it. For the most part the bowls are the same on the inside and in fact, the vanes are longer on the C which should straighten your thrust more before it hits the nozzle. I would say however that a split bowl would probably be in order for attaching a droop (I've had mixed input as to whether or not one would help on my hull) in order to help unwet more of the boat. Regardless of how many more HP he might have over 850, I really hope there is something wrong in his pump or setup, cause if not I'm not going to meet my goal with the HP I'm currently running. Then again, I also have some MPD magic on my side and kept the compression at 9.1 so I could add the blower if need be. ;-)
Good luck to you and your friend,
Chris
[This message has been edited by flat broke (edited September 27, 2001).]
H8Mondy: I'm kinda in the same spot as your buddy. A buddy and I spent two years building an '88 Hallett Vector from bare hull. Pump was demanded due to where we do most of our boating on the sandbar infested waters of Blythe. I'm running a 454 intercooled Gentry twin turbo. 625 HP @ 8 lbs. The pump is a stock Dominator 12S w/ A-AA impeller, Place diverter, ride plate, 5/8" shoe, and open center ramp loader. First time out it ran 75 @ 6000 with an A and almost no boost. It porpoised BAD! and was generally ill-handling. No boost and big RPM lead us to belive that we weren't loading the pump. So we radiused the keel 2' in front of the intake and changed the impeller to an AA that we have since trimed to between an AA and A. We added trim tabs and installed a turning fin. The tabs now eliminate porposing when I bury the nose and the turning fin has helped it to go right, not just left. Today the boat runs 71 @ 5500 w/ a full 8 lbs of boost. The Vector hull is a little over 21' and 8' wide. I don't know how much it weighs but a few have told me they're heavy. The boat was built for family (2 1/2 yr. son and 3 mo. daughter) so I'm happy. But it seems all the adolesents with their 18'ers run 70ish in Blythe. I can stay with them but I sure wouldn't mind another 3-4 MPH so I can just ever so slowly walk away from them http://free.***boat.net/ubb/smile.gif.
BDB: I got away from the water pressure issue by running two bottom pick-ups. One to a raw water pump that feeds the oil cooler, into the motor and out the double wall stainless pipes. The other feeds the inter cooler and dumps out the side.
B509L: I'm not familiar with Liberator hull. Is it air entrapment? What have you done to the pump and who did the setup?
Thx, HRr
Well BDB...good eye, I called Rick, (the boat owner) and he told me that the blower was indeed an 8-71. (the 10-71 is on our OTHER buddy's 572) I don't have any great picts of the boat, but here are a few to give you an idea of what we are working with.
first, the hull (mine)
http://www.pirate4x4.com/ubb/uploads/Mine.jpg
Whoops!! Too much 'wetted area' for sure. http://free.***boat.net/ubb/wink.gif
http://www.pirate4x4.com/ubb/uploads/Myboat.jpg
Rick's
http://www.pirate4x4.com/ubb/uploads/Rick1.jpg
and here are a couple that show wetted area, however, the place diverter was in the 'show' position, rather than the 'go' position.
http://www.pirate4x4.com/ubb/uploads/Rick2.jpg
http://www.pirate4x4.com/ubb/uploads/Rick3.jpg
But I mean, really... its spinning a AA at 6500 rpm! its NOT the Queen Mary, it should run faster than 74. Its not THAT heavy... it doesn't even have carpet! Again, mine goes 55 on 320 hp.
[This message has been edited by H8Monday (edited September 27, 2001).]
[This message has been edited by H8Monday (edited September 27, 2001).]
[This message has been edited by H8Monday (edited September 27, 2001).]
Hey there FLATBROKE I see now how shit gets started.....I NEVER said the JC was a "cheapo" replacement to the JG. Its a FACT that the JC pump is a low performance pump...PERIOD. It was designed to be installed in heavy boats that needed alot of thrust at a very low rpm to get it moving. Heavy daycruiser style boats were never intended to be fast or even quick..Maybe the word dayCRUISER should be a clue. What I also said was that a JC pump in stock form becomes NON efficient above 4000 rpm. It CAN'T handle the water volume that a JG pump can. You also stated that you don't really see a difference in the bowls except for the fact that a JG is a split bowl. I hate to argue and thats not my intention however, there IS difference between a JC and a JG. Without getting into technical stuff, the JG can handle much more volume at a much higher flow rate than a JC. I not telling you anything that Greg Shoemaker @ gsmarine won't back me up on or anyone else that makes a living doing this. Just wanted to clear that up. PEACE.
I"ve driven the boat several times. The boat NEVER porpoises, and would never be what I call 'ill handling.
With the place diverter up with about a 4ft high 'tail', the water breaks just in front of the motor. With it in the full down position, the water will break in front of the driver.
The pump does not have any shoe or rideplate. The only type of loading the pump gets is from a loader grate.
You guys think that pump mods could get this boat to see high 80's?
H8...IF I HAD THE CHOICE WITH YOURLAST POST I WOULD GIVE A SHIT HOW FAST MY BOAT WENT....IN FACT IF THAT ASS WAS AT MY HOUSE THAN I WOULD HAVE TIME TO SCREW WITH BOATS!!!!!!!!!!!AS THE GREAT RICK FLAIR WOULD SAY>>>>>WWWWWWWWWHHHHHHHHHOOOOOOOOOOOOWWWWWWWWWWWW WWWWWWWWWWWW!!!!!!!!
Anyway, thats a nice looking boat. i know in most terms you don't think that your boat is very heavy but wieght is CRITICAL in jetboats. I see boats all day long that are light as hell and haul serious ass(NOT LIKE HER ASS THOUGH) and as soon as you put someone riding shotgun, the boat drops 3-5 mph on the top end. Thats why real fast jetboats are light and small. Anyway, your boat MIGHT see 78 if the pump,shoe and plate are setup right. Just the facts...Just think of it like this...As your boat was meant to put a bunch people and coolers on board and go out and play all day in different types of water without to many hassles. Thats what the boat was built for....My boat only has room for me and a passanger and a SMALL cooler. My boat can go the same places as your BUT it will beat the crap out even Stone cold himself if he was riding in it. If it were me and I owned your boat, I would put the interior back init make it nice and comfortable, load that SWEET ass in it and go find me a nice quiet liitle cove. GET MY DRIFT? I bet the other guys would agree. Go out and get a tunnel if you wanna have a nastyass jetboat. If you can't find one, I have a few here at my shop I could make ya a deal on. PEACE BRUDDAH!!!!!!!!
Hey H8Monday, I think BDB is right.....you can't have the best of both worlds, call Eliminator or someone really knowledgable of your hull and find out what your max hull speed is and what kind of HP it takes to attain it........you'll probally find out your in the ball park. The money you are gonna spend to hit high 80's would be better spent on a different hull.....pull your motor and drop a stock unit in its place and sell it to someone to use as a day cruzer...what it was meant for and see what BDB has for sale. You'll be money and MPH ahead.
HotRodder
Liberator hulls...well just go look at a Daytona add 8" more to the transom and you'll have it.
http://nothinbutjets.homestead.com/files/10005.jpg
Here is more pic if you want to see http://nothinbutjets.homestead.com/Liberatorpic.html
[This message has been edited by Blown509Liberator (edited September 28, 2001).]
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