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What does it take to go 80mph???

BONER

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Hypothetical............

Lets say I have a 21-22' open bow jet boat. I'd like it to do around 80mph. My questions are, how much work needs to be done to the pump, how much power is needed, and would there be a huge speed difference between loaded and empty?

Thanks.
 

BONER

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^^Lol.

Here's an example. I've talked to this guy on the phone as I really like this boat. He says the boat is good for 64mph, on the chip @ 6600rpm's. I feel like there should be a lot more??? He also says the boat will jump out of the water if you pin it from a stop or a very slow roll. But they do a lot of skiing and towing. Maybe an impeller change would be good for another 6-7mph???

https://inlandempire.craigslist.org/boa/d/carrera-open-bow-jet-boat/6296574441.html
 
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Cole Trickle

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^^Lol.

Here's an example. I've talked to this guy on the phone as I really like this boat. He says the boat is good for 64mph, on the chip @ 6600rpm's. I feel like there should be a lot more??? He also says the boat will jump out of the water if you pin it from a stop or a very slow roll. But they do a lot of skiing and towing. Maybe an impeller change would be good for another 6-7mph???

https://inlandempire.craigslist.org/boa/d/carrera-open-bow-jet-boat/6296574441.html

70mph in a jet is going to be tough and take a ton of hp. 80 mph is going to take way more than that.

I would say 800+ hp and a pump to match. 1000hp would be better.
 

NicPaus

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Friend has the identical boat to that 1. No way would I want to go 80 in it. That motor looks good probably pushing the pump to its limits. To gain 10 mph it will cost more than he is asking. That is plenty of power for that hull.
 

138

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Do you have to have a Jet? Outboards will get you there with far less power and use 1/4 of the gas.

What is your price range you can spend?
 

rivrrts429

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There is no straight formula of horsepower to speed ratio with a jet. No two jet boats are ever alike because it's small details that collectively make big differences. You're talking about a design that isn't efficient to begin with so getting it to work at its absolute optimum efficiency is a science project in itself.

You've got to be careful you're not buying a donkey thinking your going to qualify for the Kentucky Derby. Nothing wrong with the donkey you've just got to know where it works at its best and be realistic about it.

Know what you want and have realistic goals in mind first. Hull make and model, realistic horsepower, size of savings account $$, and realistic goals all come into play.

You mentioned open bow. Already you're adding weight in all the wrong places for a jet if your trying to run the number on the big end. I'm not saying you can't meet your MPH goal but you make it harder and costlier with a bunch of cup holders and seat cushions in front of you.

Let's see some examples of what style and make you've got in mind?
 

RACER J

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^^Lol.

Here's an example. I've talked to this guy on the phone as I really like this boat. He says the boat is good for 64mph, on the chip @ 6600rpm's. I feel like there should be a lot more??? He also says the boat will jump out of the water if you pin it from a stop or a very slow roll. But they do a lot of skiing and towing. Maybe an impeller change would be good for another 6-7mph???

https://inlandempire.craigslist.org/boa/d/carrera-open-bow-jet-boat/6296574441.html
64mph @ 6600rpm with an A Impeller is way off, chances are the bottom of the boat isn't supplying the pump with water.
My 96' ultra open bow runs 62 at 5000rpm with an A Impeller. Lol hell, I'd sell it less motor for 10,000 and you could put all the horsepower you want in it.
Already has shoe, ride plate and hyd. Place diverter.
db2c929781463b697604b4e1d5604acb.jpg
af312250e64c90eaa5ca4eaea283c9cc.jpg
 

rivermobster

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At the beginning of summer we had a customer that bought an old Hallett jet boat. 18 footer. Pretty much a beginner boat, and that's exactly what he was. This was the first boat he'd ever owned.

I threw a new carb on it, a new ignition system and got it running. He asked me to go to the puddle with him, for the first time he took it out. He wanted me to drive it the first time out and show him the ropes.

OMG....

I truly had forgotten how ill handling a jet boat is!!! Turn to the left, turn to the right, its impossible to make one go straight at slow speed! Trying to put it back on the trailer was too scary for me. I shut it off and just floated it on to the trailer, there was no way to line it up under power.

Probably used forty bucks in gas, in two laps around the puddle. There would be no way I'd ever own a jet boat. :thumbsdown

That being said....................

IF I had an unlimited budget (cause that's what it takes to go fast in one), I'd get a California Performance hull and drop a 700ci torque monster in it, probably something from Sonnys. Then I'd take it to Brian at B&D and let him build the pump, and then have Danny Bell blueprint the bottom.

http://www.sonnysracingengines.com/engines/boat-engines/sar-680-marine-engine

This would be a solid running and handling boat, but you better have a shit load of funds!!!!!!!!


Best to Stay away from the donkeys. ;)
 

RACER J

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At the beginning of summer we had a customer that bought an old Hallett jet boat. 18 footer. Pretty much a beginner boat, and that's exactly what he was. This was the first boat he'd ever owned.

I threw a new carb on it, a new ignition system and got it running. He asked me to go to the puddle with him, for the first time he took it out. He wanted me to drive it the first time out and show him the ropes.

OMG....

I truly had forgotten how ill handling a jet boat is!!! Turn to the left, turn to the right, its impossible to make one go straight at slow speed! Trying to put it back on the trailer was too scary for me. I shut it off and just floated it on to the trailer, there was no way to line it up under power.

Probably used forty bucks in gas, in two laps around the puddle. There would be no way I'd ever own a jet boat. :thumbsdown

That being said....................

IF I had an unlimited budget (cause that's what it takes to go fast in one), I'd get a California Performance hull and drop a 700ci torque monster in it, probably something from Sonnys. Then I'd take it to Brian at B&D and let him build the pump, and then have Danny Bell blueprint the bottom.

http://www.sonnysracingengines.com/engines/boat-engines/sar-680-marine-engine

This would be a solid running and handling boat, but you better have a shit load of funds!!!!!!!!


Best to Stay away from the donkeys. ;)
Lmao. They aren't that hard to drive and it really doesn't take tons of horsepower to make a "Good" 18' jet haul ass.
My last boat was a 19' place craft with a 496ci Chevy and it ran 110, didn't think that was too bad for a mud sucker.
 

SBMech

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Every boat out there has a different hull, different layup, makes this really a non answerable question.

If you want specifics pick a boat, then find someone who can work out all the details, blue print the hull, match the drivetrain etc.

Like racing on the salt flats at Bonneville...you are only limited by your pockets and how deep they go...:p
 

port austin pirate

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Hypothetical............

Lets say I have a 21-22' open bow jet boat. I'd like it to do around 80mph. My questions are, how much work needs to be done to the pump, how much power is needed, and would there be a huge speed difference between loaded and empty?

Thanks.

I thought all jet boats ran at least 100mph;)
 

BONER

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Do you have to have a Jet? Outboards will get you there with far less power and use 1/4 of the gas.

What is your price range you can spend?

I understand the outboard argument. I just want a BBC. Not against Bravo 1 or better drive either, but I love the rooster tails from the jets.
 

BONER

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64mph @ 6600rpm with an A Impeller is way off, chances are the bottom of the boat isn't supplying the pump with water.
My 96' ultra open bow runs 62 at 5000rpm with an A Impeller. Lol hell, I'd sell it less motor for 10,000 and you could put all the horsepower you want in it.
Already has shoe, ride plate and hyd. Place diverter.
db2c929781463b697604b4e1d5604acb.jpg
af312250e64c90eaa5ca4eaea283c9cc.jpg

What would you want WITH the motor?
 

farmo83

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Texas Jet would be a good resource for this, perhaps he'll chime in.

In my expierance all any boat needs to get to 80 mph is the driver to have 3-4 more beers and the 60 mph boat will magically turn into a claimed 80 mph boat.

My Dad had a CVX 20 jet for 30 years before willing it to me, I drove it for 3-4 years before getting my Schiada. It wasn't a bowrider but it's plenty heavy. I priced out putting around 650 to it and from I remember Tom at Jet Boat performance said it would run low 70's. I would think 80 would need 750-800.
 

AzGeo

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It ran 86 MPH, right out of the box, on pump gas . (single 850 B&M 177)

It will run 100 with an 8-71 and two 850's, on pump gas .

It's all original gel coat .

I know this because I built it for the current owners, who have it for sale .
 

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Rogers Hopeful

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My 16'6" rogers with a SBC 383 with a 920 cfm carb ran 60mph this weekend with 3 200+lbs men, ice chest, and the Bimini up. Berkeley jet, A impeller at 5600 RPM
 

TexasJet

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I have a 19' Baja with a aggresor bowl and a stock B stainless impeller. It has a HTP straight snoot. The motor is a 496 hydraulic roller that dynoed 570 HP. That motor pushed this heavy vhull 71.1 mph on a gps speedo. No bull shit.
 

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brgrcru

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At the beginning of summer we had a customer that bought an old Hallett jet boat. 18 footer. Pretty much a beginner boat, and that's exactly what he was. This was the first boat he'd ever owned.

I threw a new carb on it, a new ignition system and got it running. He asked me to go to the puddle with him, for the first time he took it out. He wanted me to drive it the first time out and show him the ropes.

OMG....

I truly had forgotten how ill handling a jet boat is!!! Turn to the left, turn to the right, its impossible to make one go straight at slow speed! Trying to put it back on the trailer was too scary for me. I shut it off and just floated it on to the trailer, there was no way to line it up under power.

Probably used forty bucks in gas, in two laps around the puddle. There would be no way I'd ever own a jet boat. :thumbsdown

That being said....................

IF I had an unlimited budget (cause that's what it takes to go fast in one), I'd get a California Performance hull and drop a 700ci torque monster in it, probably something from Sonnys. Then I'd take it to Brian at B&D and let him build the pump, and then have Danny Bell blueprint the bottom.

http://www.sonnysracingengines.com/engines/boat-engines/sar-680-marine-engine

This would be a solid running and handling boat, but you better have a shit load of funds!!!!!!!!


Best to Stay away from the donkeys. ;)

let me know the next time your driving a jet at the river? so I can make sure to get the hell off the river. :D
 

rivermobster

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You can take my 19' cp for a spin anytime. I think you will have a more fun then your last outing with a jet ;)
Oh hell yes! I wanted to build one of those at one time. Even talked to B&D about it.

I wanted a naturaly asperated engine to go an Honest 100mph.

We figured we needed around 700ci to do it reliably on pump gas. When I penciled that out, it was beyond my budget at the time.

I'd love to go for a ride. You gonna be out this weekend?
 

brgrcru

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Oh hell yes! I wanted to build one of those at one time. Even talked to B&D about it.

I wanted a naturaly asperated engine to go an Honest 100mph.

We figured we needed around 700ci to do it reliably on pump gas. When I penciled that out, it was beyond my budget at the time.

I'd love to go for a ride. You gonna be out this weekend?

Just came back from Parker Wednesday .
Most likely October and thanksgiving

650-700 hp in a full interior lake layup 19 ' will get you real close. Might need a little more.
Mines been 114 with a 1000 hp
The current motor is 582 ci 700hp pump gas hyd roller and will run 94/95mph
Nice just changing oil and plugs.
I'm way Over the race gas , high maintenance. Bs.
Chased a 100 mph through 4 motors. :grumble:
Got there and went the other way. Much happier.
But definetly one day , if you see us , hit me up.
My weekends in Parker are usually Sunday --Wednesday ,
 

rivermobster

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Just came back from Parker Wednesday .
Most likely October and thanksgiving

650-700 hp in a full interior lake layup 19 ' will get you real close. Might need a little more.
Mines been 114 with a 1000 hp
The current motor is 582 ci 700hp pump gas hyd roller and will run 94/95mph
Nice just changing oil and plugs.
I'm way Over the race gas , high maintenance. Bs.
Chased a 100 mph through 4 motors. :grumble:
Got there and went the other way. Much happier.
But definetly one day , if you see us , hit me up.
My weekends in Parker are usually Sunday --Wednesday ,
I hear ya. Kinna why I love my toon. [emoji12]
 

War Canoe

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Do you have to have a Jet? Outboards will get you there with far less power and use 1/4 of the gas.

What is your price range you can spend?

My stock 300xs took my 19' Cougar to 113 mph getting 4 mpg.

I don't want to rub it in, but that came with a warranty as well. Did I mention that chicks dig outboards?

I'll go back to my Outboard Church now..;)
 

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BONER

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How much money do you think you'd have to sink into a stock Berkley to handle 800hp?
 

ONE-A-DAY

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My rule of thumb is $1000 per mph, its worked out to be pretty accurate on all of the builds I have done. To go from 72 to 117 cost me right around $45,000, and I was able to recoup $8000 of that when I sold the boat. Brilliant.
 

rivrrts429

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How much money do you think you'd have to sink into a stock Berkley to handle 800hp?


Depends on which Berkeley but if we’re talking about a split bowl then probably $2.5k-$3k with hardened shaft, hi-helix impeller, etc...

I’d imagine with 800hp your also going to go with a pop-off or ratchet type safety device so the price goes higher.
 

BONER

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My rule of thumb is $1000 per mph, its worked out to be pretty accurate on all of the builds I have done. To go from 72 to 117 cost me right around $45,000, and I was able to recoup $8000 of that when I sold the boat. Brilliant.

$45k total, or in the jet by itslef????
 

TexasJet

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I just happened to see this thread. I have a 19' Baja BR with a 496 CI Chevy that dynoed 565 HP. The pump is bone stock with an agressor B impeller. The pump has a straight snoot from HTP. It runs 71 MPH on Gps. 93 octane fuel (in Texas). About 10.5 to 1 compression.
imgBoat001.jpg
 

Dalton

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i have a 21 commander jet, goes about 60 with what I suspect is around 400 hp, having a 600 hp engine built right now, I don't think ill gain more than 5 mph maybe 10, im adding hp just for ease of boating and cruising easier
 

jetboatperformance

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Hypothetical............

Lets say I have a 21-22' open bow jet boat. I'd like it to do around 80mph. My questions are, how much work needs to be done to the pump, how much power is needed, and would there be a huge speed difference between loaded and empty?

Thanks.
Your Hypothetical needs a whole lot more basic info to address however , likely with 7 to 8 hundred horsepower, jet work , trim, bottom work, lightening and a quite q bit more for it to get there , question I would have is why, not trying to be a downer , a 21 open bow is a family "truckster" not a drag boat , safety would be a concern as well .... 80 + is easily obtained in a small light boat
 

LazyLavey

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Don't you guys remember that guy back in the 70s who had a brother-in-law who had a Kona jet boat running a stock 460 with a Berkley jet and a jetavator?

It ran 80mph.. must have been a "factory fluke"... went so fast the oil breathers would fall off!

I remember a few of those guys

Every once in a while I hear about another "factory fluke"
 

AzGeo

Fair winds and following seas George.. Rest Easy..
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When this thread is finally done, I'll be buying a few of the "THUMBS" around here .

Never can have too much power or luck, but apparently "THUMBS" are better than both ........HA HA
 

BONER

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Your Hypothetical needs a whole lot more basic info to address however , likely with 7 to 8 hundred horsepower, jet work , trim, bottom work, lightening and a quite q bit more for it to get there , question I would have is why, not trying to be a downer , a 21 open bow is a family "truckster" not a drag boat , safety would be a concern as well .... 80 + is easily obtained in a small light boat

I understand what you're saying. Not sure I'd do 80 with the Family on board. But I'd definitely let her eat if it was just me and a buddy ripping up and down the river...

I'm a speed junky. Have had multiple 9 sec street cars. To me, having a boat with a big block, and it not being atleast an 80mph rig is a waste of my time and money. Sure I'm getting into this hobby as a Family thing, but the vessel must perform to my standards as well.

Since I've started this thread, I've been researching a ton. Starting to lean towards a prop boat because the jets just don't seem to give the performance I'm looking for without a shit ton of work and testing.
 

No Butt No Putt

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I had a 1981 18ft Crusader with 600hp and a pretty good setup pump and the boat ran 90 on gps. But it was light. I think it would be hard to see 80 out of a 21-22ft jet boat.
 

73mandella

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I had a 1981 18ft Crusader with 600hp and a pretty good setup pump and the boat ran 90 on gps. But it was light. I think it would be hard to see 80 out of a 21-22ft jet boat.

Or you could do it the easy way and build a big block ford with 691 hp (WestTech dyno), blueprint a Dominator pump, put it in a '77 Caribbean, plant you foot in it, and see the GPS speedometer read 92 mph. Lots more fun this way.
 

SBMech

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I had a 1981 18ft Crusader with 600hp and a pretty good setup pump and the boat ran 90 on gps. But it was light. I think it would be hard to see 80 out of a 21-22ft jet boat.

It's not hard at all. Just expensive. :D
 
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