SoCal Jet Boats

Discussion => The No Wake Zone => Topic started by: ChaseThisToo on May 13, 2016, 09:02:21 AM

Title: Chasing the all mighty MPH
Post by: ChaseThisToo on May 13, 2016, 09:02:21 AM
I'm hoping a few of you seasoned veterans can help a new guy out.  To say I'm green is an understatement.  I'm here to learn and any help is appreciated.

I have an '88 20.5 Carrera Elite family cruiser and I love it.  She rides nice and keeps my wife happy.  My issue is I want to make her faster.  I have a great motor builder that used to build all Teague Marine's off shore motors and currently builds all my race motors for my off road program.  He keeps telling me that I need to build the pump before the motor.  He says he can build a big old motor for it but its only going to pump so much water...makes sense.

My question for you guys, is 70mph even reachable in a boat like mine? (she currently runs 55 with just me and 47 with the family and full tanks)  I guess it depends on what I do to it but I'm trying to get a base idea of what I should do before i start tearing into it.  Thanks again and hope to see you guys out on the water.

[attachimg=1][attachimg=2]
Title: Re: Chasing the all mighty MPH
Post by: steves86ta on May 13, 2016, 09:12:39 AM
"the power is in the pump"

With that said, you can only make a pump work so good with so much hp

If you have a good tight pump, then the more power you put in front of it, the more thrust you will get.

Is 70 possible in your hull? Yes. Im sure it will take a pretty decent amount of HP. But its doable.

A solid 650hp should get you there i would think. But that is a pretty heavy hull.

What RPM are you doing now? What impeller?
Title: Re: Chasing the all mighty MPH
Post by: GT Jets on May 13, 2016, 09:26:03 AM
I'm hoping a few of you seasoned veterans can help a new guy out.  To say I'm green is an understatement.  I'm here to learn and any help is appreciated.

I have an '88 20.5 Carrera Elite family cruiser and I love it.  She rides nice and keeps my wife happy.  My issue is I want to make her faster.  I have a great motor builder that used to build all Teague Marine's off shore motors and currently builds all my race motors for my off road program.  He keeps telling me that I need to build the pump before the motor.  He says he can build a big old motor for it but its only going to pump so much water...makes sense.

My question for you guys, is 70mph even reachable in a boat like mine? (she currently runs 55 with just me and 47 with the family and full tanks)  I guess it depends on what I do to it but I'm trying to get a base idea of what I should do before i start tearing into it.  Thanks again and hope to see you guys out on the water.

(Attachment Link) (Attachment Link)

OMHO, 70 is a lofty goal.

That hull is designed for the family of four to go 55 mph and do it in style and comfort.

For that rig to do an honest 70, it needs virtually everything.

I would not set the pump back,  but a show,  rideplate,  droop, Diverter,  stainless impeller,  inducer,  good loader ate all going to be needed to support the 700 or so hp to get you to 70.

I own a 92 Carrera Elite 20.5 that I have been building for years (total budget build) and my intention is to get it to go 72mph. With a small block and Alpha 1 gen 2 outdrive.

Just in the interior alone I was able to trim an estimated 400 pounds,  another 150 in the construction of the floor.

Using a small block saved me another 200. That's like going from 9 people to only one horse jockey.

Weight is the enemy. Especially on a jet.

How fast is it now and what mods have been done?
Any estimation on horsepower?

How thick is your wallet?

That last one stops most. Lol

One thing to remember,  to go fast means more fuel,  more noise,  more breakage,  fewer drivers and most importantly, less reliability.

If the wife is ok with all that,  your 90% there. Lol

Me personally,  I would build a hot rod.  On the end, it would probably be cheaper. Those divorce lawyers to do much pro Bono.

GT
Title: Re: Chasing the all mighty MPH
Post by: steves86ta on May 13, 2016, 09:30:37 AM
just spray the living shit out of it  :thumbup:  :thumbup:  :thumbup:
Title: Re: Chasing the all mighty MPH
Post by: FordLover on May 13, 2016, 09:32:02 AM
Hey Glenn, why 72 mph? Not 70? Not 75? But 72?
Title: Re: Chasing the all mighty MPH
Post by: ChaseThisToo on May 13, 2016, 09:34:26 AM

What RPM are you doing now? What impeller?

Assuming the tach is correct right around 5 grand. Its a 454 BBC.  I was told it has an A/B impeller
Title: Re: Chasing the all mighty MPH
Post by: steves86ta on May 13, 2016, 09:38:20 AM
Assuming the tach is correct right around 5 grand. Its a 454 BBC.  I was told it has an A/B impeller

15 mph in your hull will take a lot more thrust. That means more rpm or a bigger impeller. A bigger impeller, means more HP to spin it.

Its possible but all of the things GT said apply.

Though one, i am curious, why does he NEED a stainless impeller? Why not an aluminum AA that he can spin to 5k or 5500 with more power?
Title: Re: Chasing the all mighty MPH
Post by: ChaseThisToo on May 13, 2016, 09:41:33 AM
How fast is it now and what mods have been done?
Any estimation on horsepower?

How thick is your wallet?


I bought the boat last year and haven't touched it...which is a miracle all by itself.

Here is what I know...

It will run 55 with just me in it topped out.  I don't know if there are any mods done to the motor but she feels tight and not beat on.

No idea on horse power.

I have a budget in mind of 5k for both motor and pump but don't know how far that will get me.

I guess my ultimate goal is not to be full throttle everywhere I go.  I'd like to cruise around 55 and if I need it have more to go.  70mph was just my goal...you always have to set them just out of reach.
Title: Re: Chasing the all mighty MPH
Post by: steves86ta on May 13, 2016, 09:44:10 AM
according to the impeller chart, if you have an AB now, youre making about 400 hp. Probably a stock 454
Title: Re: Chasing the all mighty MPH
Post by: GT Jets on May 13, 2016, 09:45:20 AM
I bought the boat last year and haven't touched it...which is a miracle all by itself.

Here is what I know...

It will run 55 with just me in it topped out.  I don't know if there are any mods done to the motor but she feels tight and not beat on.

No idea on horse power.

I have a budget in mind of 5k for both motor and pump but don't know how far that will get me.

I guess my ultimate goal is not to be full throttle everywhere I go.  I'd like to cruise around 55 and if I need it have more to go.  70mph was just my goal...you always have to set them just out of reach.

Don't take this the wrong way,  not insulting your intelligence,  but $5k will get you just a tick past 60mph.

JMHO

GT
Title: Re: Chasing the all mighty MPH
Post by: ChaseThisToo on May 13, 2016, 09:48:53 AM
Don't take this the wrong way,  not insulting your intelligence,  but $5k will get you just a tick past 60mph.

JMHO

GT

No offense taken.  I'm new to this and have no idea of what things cost. 

The problem is I have to many damn hobbies and I'm currently building another race car so most of the coin is tied up in that.
Title: Re: Chasing the all mighty MPH
Post by: FordLover on May 13, 2016, 09:50:52 AM
No offense taken.  I'm new to this and have no idea of what things cost. 

The problem is I have to many damn hobbies and I'm currently building another race car so most of the coin is tied up in that.

Then enjoy the crap out of the nice cruiser that you have this summer. Then in the future build you a hot rod jet that does 80! Ya!! More is better!!
Title: Re: Chasing the all mighty MPH
Post by: GT Jets on May 13, 2016, 09:55:53 AM
Hey Glenn, why 72 mph? Not 70? Not 75? But 72?

I knew that would raise an eyebrow.

My dad, way back when I had my boat shop, found a Crusader 23 on the side of the road for sale.

He called me and said "can you make it go 70mph?".

I said "it's only money".lol

He bought the boat and the trailer (tri axle Trail Rite brand new) for $1,500.

I wanted to go with a 5.7L magnum efi Mercruiser repower package at 350 hp(had one in the shop brand new).

He wanted "big block power and thru hull exhaust".

The boat has a best GPS speed of 71mph with a raised X dimension on a Bravo I and a 454. He is totally happy.  We have about $13k in the boat doing most of the work ourselves (you should see the motor mounts I built for it).

Anyway,  I built an iron headed 5.7 Vortec that makes 398 hp at 5,300 Rpm on a hydro dynamometer  (uses water for the medium).

That Carrera has to do 72. For the record,  I'm in my Carrera  $820 with a tube Extreme trailer, but I'm in it for four years.

Make sense?

GT

Title: Re: Chasing the all mighty MPH
Post by: FordLover on May 13, 2016, 10:04:30 AM
Perfect sense! Thanks! Carry on
Title: Re: Chasing the all mighty MPH
Post by: steves86ta on May 13, 2016, 10:46:47 AM
I knew that would raise an eyebrow.

My dad, way back when I had my boat shop, found a Crusader 23 on the side of the road for sale.

He called me and said "can you make it go 70mph?".

I said "it's only money".lol

He bought the boat and the trailer (tri axle Trail Rite brand new) for $1,500.

I wanted to go with a 5.7L magnum efi Mercruiser repower package at 350 hp(had one in the shop brand new).

He wanted "big block power and thru hull exhaust".

The boat has a best GPS speed of 71mph with a raised X dimension on a Bravo I and a 454. He is totally happy.  We have about $13k in the boat doing most of the work ourselves (you should see the motor mounts I built for it).

Anyway,  I built an iron headed 5.7 Vortec that makes 398 hp at 5,300 Rpm on a hydro dynamometer  (uses water for the medium).

That Carrera has to do 72. For the record,  I'm in my Carrera  $820 with a tube Extreme trailer, but I'm in it for four years.

Make sense?

GT
Its been a while, but the bahner has done 72 with a vortec headed small block...

One of the best ways to go with a small block imo. We just need to throw a smaller cam in it
Title: Re: Chasing the all mighty MPH
Post by: mash on it on May 13, 2016, 12:18:50 PM
Bravo?
Alpha?

These speeds meaningless in relation to a BERKELEY jet drive.

At ~500hp on a big 21', I was at 57, gps'd, upriver, full of fuel, coolers, gear, 4 people, etc.

As Glenn said, weight is a huge factor on a jet.

I've researched into my hull, and it good to about 70, then it gets unstable. How much HP? I don't know, lot$, and then $ome, I'd guess.

Reliability goes down as HP goes up, too

Dan'l

Title: Re: Chasing the all mighty MPH
Post by: GT Jets on May 13, 2016, 01:26:35 PM
Bravo?
Alpha?

These speeds meaningless in relation to a BERKELEY jet drive.

At ~500hp on a big 21', I was at 57, gps'd, upriver, full of fuel, coolers, gear, 4 people, etc.

As Glenn said, weight is a huge factor on a jet.

I've researched into my hull, and it good to about 70, then it gets unstable. How much HP? I don't know, lot$, and then $ome, I'd guess.

Reliability goes down as HP goes up, too

Dan'l

They actually aren't meaningless,  I have the same hull and was able to trim a ridiculous amount of fat from it,  that was the intent of my post. I was asked a specific question about my boat,  I answered it.

Back off on the Rock Stars there Bro. Lol
Title: Re: Chasing the all mighty MPH
Post by: mash on it on May 13, 2016, 01:54:19 PM
No rock stars here-

I guess I need to try a different prop.

Dan'l

Title: Re: Chasing the all mighty MPH
Post by: AngryJosh on May 18, 2016, 09:36:52 PM
Well I'll chime in but all its going to do is back up everything everyone already stated...
First off remember the black boat parked next to you at the Avi? Thats mine. 21ft open bow with heavy ass hull, heavy ass interior, stereo blah blah blah... Needless to say shes a big girl as far as jet boats go! That being said Im deep in the 70's full of fuel and loaded with 4 people and coolers. But its costed me cubic dollars. I went 509" of chevy with a huffer on top pushing through a chiller, roller, aluminum heads etc etc... Put this same motor in these little 18 footers and I could play on the top ten list. But for me; entertaining friends and going farther distances mean more to me than an occasional blip past 90mph. Theres not a trip I go out where I dont think about the good ol days of a stock 454 and a reliable 50mph and 50 gallons of fuel lasted all day!!!
I think my point is this, yours and my boats were designed to haul a few people around the lake or river all day but not really a race hull. If you want to throw a few bucks at the pump I say go for it. But Id reconsider chasing 70+mph in a cruiser. JMHO
Free advice is worth what you pay for it...nuthin!! Have fun
Beautiful boat btw


One fast station wagon!!!
Title: Re: Chasing the all mighty MPH
Post by: el mojado on May 18, 2016, 10:37:56 PM
Id be happy doing 60 in my tank.   But im not even sure if im hitting 50!!!
Title: Re: Chasing the all mighty MPH
Post by: BoatsNhoes on May 19, 2016, 11:51:52 AM

Well I'll chime in but all its going to do is back up everything everyone already stated...
First off remember the black boat parked next to you at the Avi? Thats mine. 21ft open bow with heavy ass hull, heavy ass interior, stereo blah blah blah... Needless to say shes a big girl as far as jet boats go! That being said Im deep in the 70's full of fuel and loaded with 4 people and coolers. But its costed me cubic dollars. I went 509" of chevy with a huffer on top pushing through a chiller, roller, aluminum heads etc etc... Put this same motor in these little 18 footers and I could play on the top ten list. But for me; entertaining friends and going farther distances mean more to me than an occasional blip past 90mph. Theres not a trip I go out where I dont think about the good ol days of a stock 454 and a reliable 50mph and 50 gallons of fuel lasted all day!!!
I think my point is this, yours and my boats were designed to haul a few people around the lake or river all day but not really a race hull. If you want to throw a few bucks at the pump I say go for it. But Id reconsider chasing 70+mph in a cruiser. JMHO
Free advice is worth what you pay for it...nuthin!! Have fun
Beautiful boat btw


One fast station wagon!!!
I agree well put sir"  55 mph blasting stereo  and cold ass beers.. I'll take that all day. . 😎👍🍻 


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Title: Re: Chasing the all mighty MPH
Post by: TexasJet on May 28, 2016, 05:44:24 PM
I've got a '79 19' Baja with a 496 ci making 565 hp. I have a B stainless impeller and a tight pump. The pump has a straight snoot from HiTechPerformance. It also has a ride plate. I have an inducer also.

Engine exhaust is thru transom Lightning Headers. It runs 71 on GPS. As you can see it's a heavy boat but the pump and motor make it all work.

Your aluminum impeller will probably handle the load until one time you are hauling ass and unload the pump going over a wave. When you land back in the water and reload the impeller is when you are going to have a hand grenade type event. Maybe not the first time but eventually. Stainless or at least brass is a must.

5 grand is a start. But we all go over budget. 
Title: Re: Chasing the all mighty MPH
Post by: NEVERDONE on June 08, 2016, 12:18:03 PM
Anyway you look at it at least you have a nice looking boat. Being bit by the speed bug can hurt. How do you think I feel, i just did a blower install for my Dad and he is turning close to 100 while I'm the 70's with the same exact hull....SMH


IMO, I would put a small blower on it, something that you won't have to do a ton of other work and you will likely gain a min. of 5 MPH and maybe 8-10, maybe. Someone made a good point about the increased maintenance that goes hand in hand with more HP, sometimes its just nice to fill it up with fuel and go.
Title: Re: Chasing the all mighty MPH
Post by: 79 sprint on June 28, 2016, 05:41:55 PM
What's up guys I have a 79 eliminator sprint Berkeley  drive the drive has been blue printed  to turn down the clearance  for less cavitation  powered  by a 460 30 over that's pretty hot with tunnel  ram an 2 650 holly  my problem  I'm having is when I'm on it it handles great till I'm getting pretty  high in mph don't know how high haven't GPS it but it starts  to get out of control  nose wants to dive in an get squirlie  on me what would be my best bet to get the handling better or have I just gotten the pump an drive  to out perform  my haul ?
Title: Re: Chasing the all mighty MPH
Post by: 79 sprint on June 28, 2016, 05:43:42 PM
My 79 eliminator sprint
Title: Re: Chasing the all mighty MPH
Post by: jimpen on June 28, 2016, 05:59:49 PM
What's up guys I have a 79 eliminator sprint Berkeley  drive the drive has been blue printed  to turn down the clearance  for less cavitation  powered  by a 460 30 over that's pretty hot with tunnel  ram an 2 650 holly  my problem  I'm having is when I'm on it it handles great till I'm getting pretty  high in mph don't know how high haven't GPS it but it starts  to get out of control  nose wants to dive in an get squirlie  on me what would be my best bet to get the handling better or have I just gotten the pump an drive  to out perform  my haul ?
  Sounds like a setup issue to me.
Title: Re: Chasing the all mighty MPH
Post by: 79 sprint on June 28, 2016, 06:00:38 PM
As fare as what
Title: Re: Chasing the all mighty MPH
Post by: jimpen on June 28, 2016, 06:07:15 PM
It could be a lot of things. Shoe,loader,ride plate diverter angle. The nose should not be in the water at high speeds. Are you sure it's not chime walking?  There is quite a few guys with sprints on here and never heard anyone complain of this.


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Title: Re: Chasing the all mighty MPH
Post by: capogniracing on June 28, 2016, 06:09:34 PM

As fare as what
Does it have a shoe, ride plate, loader, and how far is it sticking below keel.


BECKY WITH THE GOOD HAIR!
Title: Re: Chasing the all mighty MPH
Post by: capogniracing on June 28, 2016, 06:12:38 PM
We built a 78 sprint with blower deal about a year ago and ran really well for what it was. Had a shoe, ride plate, and a decent loader in it and ran in the 85-90 mark. Never did anything funny on the top end. But was hard to get aired out with that delta pad.


BECKY WITH THE GOOD HAIR!
Title: Re: Chasing the all mighty MPH
Post by: 79 sprint on June 28, 2016, 06:13:19 PM
Nothing but the jet drive no ride plate original  loader
Title: Re: Chasing the all mighty MPH
Post by: capogniracing on June 28, 2016, 06:14:41 PM
.


BECKY WITH THE GOOD HAIR!
Title: Re: Chasing the all mighty MPH
Post by: 79 sprint on June 28, 2016, 06:19:29 PM
It stays on plane with the nose up till high speed then acts like it's is nosing in almost like the ass is coming out of the water an try to steer to the left a little  on its own I think my mph is just to hight for not having the ride plate an all the other goodies
Title: Re: Chasing the all mighty MPH
Post by: capogniracing on June 28, 2016, 06:51:04 PM

It stays on plane with the nose up till high speed then acts like it's is nosing in almost like the ass is coming out of the water an try to steer to the left a little  on its own I think my mph is just to hight for not having the ride plate an all the other goodies
Would you simulate it to porposing


BECKY WITH THE GOOD HAIR!
Title: Re: Chasing the all mighty MPH
Post by: 79 sprint on June 28, 2016, 07:04:12 PM
I don't even know what that is lol sorry
Title: Re: Chasing the all mighty MPH
Post by: capogniracing on June 28, 2016, 07:08:24 PM

I don't even know what that is lol sorry
lol no biggie, do you have a place diverter on the boat


BECKY WITH THE GOOD HAIR!
Title: Re: Chasing the all mighty MPH
Post by: 79 sprint on June 28, 2016, 07:11:04 PM
No just the stock jet with internal milling to turn down  the clearance 
Title: Re: Chasing the all mighty MPH
Post by: capogniracing on June 28, 2016, 07:16:55 PM

No just the stock jet with internal milling to turn down  the clearance
Might wanna try a place diverter. I believe Sean doesn't have a ride plate on his and it rides fine without it. He also went back between a droop and straight snoot. Try giving him a pm 81sprint to verify his set up


BECKY WITH THE GOOD HAIR!
Title: Re: Chasing the all mighty MPH
Post by: 79 sprint on June 28, 2016, 07:18:53 PM
Perfect  thank you the boat is completely  original other than the jet work an motor work it probably  hasn't been on the water 20 times since pulled off the show room in 79
Title: Re: Chasing the all mighty MPH
Post by: capogniracing on June 28, 2016, 07:20:08 PM

Perfect  thank you the boat is completely  original other than the jet work an motor work it probably  hasn't been on the water 20 times since pulled off the show room in 79
Yes I saw that! Very nice time capsuled piece. Love the brown diamond stick Interrior. 👍🏻👍🏻 very nice float bud!!


BECKY WITH THE GOOD HAIR!
Title: Re: Chasing the all mighty MPH
Post by: 79 sprint on June 28, 2016, 07:22:57 PM
I'm probably  going to end up getting  rid of it it's to fast for the wife she's wanting a wake boat I'm probably  going to try trading for a mid engine  nautique or something  similar  if you know anyone an thank you for your help an info
Title: Re: Chasing the all mighty MPH
Post by: capogniracing on June 28, 2016, 07:23:45 PM

I'm probably  going to end up getting  rid of it it's to fast for the wife she's wanting a wake boat I'm probably  going to try trading for a mid engine  nautique or something  similar  if you know anyone an thank you for your help an info
No problem GLWS!!


BECKY WITH THE GOOD HAIR!
Title: Re: Chasing the all mighty MPH
Post by: vwagon13 on June 28, 2016, 08:54:26 PM
I'm probably  going to end up getting  rid of it it's to fast for the wife she's wanting a wake boat I'm probably  going to try trading for a mid engine  nautique or something  similar  if you know anyone an thank you for your help an info

Yea Buddy.. I'd have to think about that one.
Title: Re: Chasing the all mighty MPH
Post by: 79 sprint on June 28, 2016, 09:08:09 PM
Lol why do you say that
Title: Re: Chasing the all mighty MPH
Post by: steves86ta on June 28, 2016, 09:10:25 PM
You should be able to run some decent mph without a ride plate. Your description almost sounds like a forn of porpoising to me.

Split bowl?
Title: Re: Chasing the all mighty MPH
Post by: 77_liberty on June 28, 2016, 09:26:03 PM
I'm in a semi v hull as well. I can run from 50-85mph and my hull is as stable at 80 as it is at 50. I'm running a loader a droop and a place diverter. No ride plate no shoe. That'll be my next upgrade maybe in the winter. Shooting for that 90 mark. Also just a thing to think about I like to run my place diverter up to gain some lift and speed but I will run it all the way down in the chop and doesn't nose dive or get unstable. I'd say you got something going on are both fins on the intake??


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Title: Re: Chasing the all mighty MPH
Post by: mattson on June 29, 2016, 06:07:09 AM
Check and see if the  bottom has a hook in it!
Title: Re: Chasing the all mighty MPH
Post by: Blue2184 on June 29, 2016, 06:24:23 AM
Kinda sounds like he doesn't have enough hp to carry the nose?


Sent from my shop setting in my boat making motor noises
Title: Chasing the all mighty MPH
Post by: JordanDangerfield on June 29, 2016, 09:06:21 AM
I doubt it's a horsepower deal. I had a '78 Eliminator Bubbledeck, which is the same delta pad bottom as this boat and I was running ~350hp. Mine only ran up to 65ish, but I never felt a hint of the boat doing anything weird.

Stock Berk JC, rock grate, and diverter.

A diverter is never a bad idea.




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