How much HP power will a 12JE handle

[CVX20Dustin]

I have a Carlson CVX20 with a 460 and a 12JE pump with loader intake. I was told that its useless to build my motor more then 500 HP. Because the pump won't handle it do to the small intake is this true.
Will stock exhaust log handle 500 HP or more?
Thanks

[Squirtin Thunder]

The exhaust will cosst you HP at higher RPM. So that being a fact you will want to make more power on the lower RPM range. I would biuld as muck power as you want, I would also have the impeller detailed. Say you are turning 4600rpms right now with an "A" impeller, I would have it detailed and cut down to a "AB" and you should turn about 4400 -4600 t the same speed or a bit faster. Being that you are running a 460 the cheepest things you can do is to move the cam timing strieght up, it is worth about 50hp. There is a bolt on shoe and ride plate that HTP offers. Roostwear has used this and was happy with the result, just don't do any grinding on the housing fill with putty to smooth transitions. If you can tell me more about your current engine combo.
Jim

[TexasJet]

I have a 19' Baja with a JE pump. My motor puts out about 550 HP. With the proper mods a JE will hand more power no problem. Call an expert, Duane at Hi-Tech Performance 316-794-8616. He worked on my pump and it made a world of difference. Another guy with a strong reputation is Garry Snow, 254-889-3336. Hope this helps you.

[Squirtcha?]

The exhaust will cosst you HP at higher RPM. So that being a fact you will want to make more power on the lower RPM range. I would biuld as muck power as you want, I would also have the impeller detailed. Say you are turning 4600rpms right now with an "A" impeller, I would have it detailed and cut down to a "AB" and you should turn about 4400 -4600 t the same speed or a bit faster. Being that you are running a 460 the cheepest things you can do is to move the cam timing strieght up, it is worth about 50hp. There is a bolt on shoe and ride plate that HTP offers. Roostwear has used this and was happy with the result, just don't do any grinding on the housing fill with putty to smooth transitions. If you can tell me more about your current engine combo.
Jim
Definitely agree with the exhaust thing, although his boat doesn't lend itself too well to headers (unless he could run water jacketed and keep the engine cover).
However I don't know if he'd want to cut that impeller Jim. The CVX20 (Glastron Carlson) is a big heavy boat. I'm thinking he'd want to be around a AA or possibly A impeller. Anything smaller would probably cost him on the lower end of things, possibly even to the point where he couldn't pull tubers or skiers/wakeboarders. His boat is a different animal than most of ours here.
http://www.classicglastron.com/77gl-carlson-cvx20small.jpg

[Squirtin Thunder]

Definitely agree with the exhaust thing, although his boat doesn't lend itself too well to headers (unless he could run water jacketed and keep the engine cover).
However I don't know if he'd want to cut that impeller Jim. The CVX20 (Glastron Carlson) is a big heavy boat. I'm thinking he'd want to be around a AA or possibly A impeller. Anything smaller would probably cost him on the lower end of things, possibly even to the point where he couldn't pull tubers or skiers/wakeboarders. His boat is a different animal than most of ours here.
http://www.classicglastron.com/77gl-carlson-cvx20small.jpg
I forgot that those things were on the heavy side.

[CVX20Dustin]

Yes, the thing is heavy but it stays hooked up in the water. The stock motor (very tried 28 oil psi WO 325 HP 460) runs 4700-4800 RPM at full throttle and I think it was running 50 MPH and I don't Know what impellar it has. I have been reading your guys post on 460 and have gotten a lot of good info. I will be rebuilding the pump and the motor 500HP. I hope to get up to 60 to 65 MPH is this a real goal for me.
Jetboatperformane told me that the pump could only handle 500 HP and a little over 5000 RPM. DO these guys Know what there talking about. I Know the exhaust Logs don't help, maybe next year a set of water jacketed header to much $ this year.
What is cam timing streight up?
Thats just like my boat in the picture same color and very thing.

[Squirtcha?]

Actually that 325 hp is probably on the optimistic side, especially if the motor's tired. Weak rings, worn valves/seats, sloppy bearings etc etc. and that power's dropped off pretty good over the years. In fact I'm not so sure that it ever had 325 hp, even when it was new.
In my opinion, I'd believe 60-65 mph is a very realistic goal with 500 hp.
I'll let Jim explain the cam timing thing since he opened that can o worms.
Incidently, I've always really liked the CVX20. I think it's styling was ahead of it's time. Very cool looking boats.
http://groups.msn.com/_Secure/0bADrAmwhoCN941PZ4UoArSvLZUf0ns64QYw5AwrKbgPRoGgI2 SM!jOcClql3BSvdxmb0UCU!o2xCjpSwD1GazpJgSVIFGEnk5LJ QcqcVKjFcud20Rb4lW49mDITkr6vJdwkaKUtTWtAQM0sV9mnjW GcrWjjXlcPc/Bilder%20N%C3%BCrburgBoot%20005.jpg?dc=46755054058 35509091

[Squirtin Thunder]

Yes, the thing is heavy but it stays hooked up in the water. The stock motor (very tried 28 oil psi WO 325 HP 460) runs 4700-4800 RPM at full throttle and I think it was running 50 MPH and I don't Know what impellar it has. I have been reading your guys post on 460 and have gotten a lot of good info. I will be rebuilding the pump and the motor 500HP. I hope to get up to 60 to 65 MPH is this a real goal for me.
Jetboatperformane told me that the pump could only handle 500 HP and a little over 5000 RPM. DO these guys Know what there talking about. I Know the exhaust Logs don't help, maybe next year a set of water jacketed header to much $ this year.
What is cam timing streight up?
Thats just like my boat in the picture same color and very thing.
OK, Yes those guys are on the ball at Jetboatperformance. You can look at the thrust bearing retainer and you will see a tagon the top of it. That tag is what will tell us what impeller it has unless it has been replaced. There is a bit of porting that can be done to the exhaust manifolds that will help. What year is the engine ??? Most likely the cam timing is about 4 - 8 degrees retarded, this is an emisions deel that Ford did to help burn the unburned fuel. It ends up super heating the exhaust. And it also hurts performance. I have seen almost 65hp on an engine Dyno from this change and up to 50hp on a chassis dyno.

[Squirtin Thunder]

I have a Carlson CVX20 with a 460 and a 12JE pump with loader intake. I was told that its useless to build my motor more then 500 HP. Because the pump won't handle it do to the small intake is this true.
Will stock exhaust log handle 500 HP or more?
Thanks
Easy test !!! Take the loader what ever type it is off and run it with the stock grate. If there is an improvement it doesn't help.

[CVX20Dustin]

OK, Yes those guys are on the ball at Jetboatperformance. You can look at the thrust bearing retainer and you will see a tagon the top of it. That tag is what will tell us what impeller it has unless it has been replaced. There is a bit of porting that can be done to the exhaust manifolds that will help. What year is the engine ??? Most likely the cam timing is about 4 - 8 degrees retarded, this is an emisions deel that Ford did to help burn the unburned fuel. It ends up super heating the exhaust. And it also hurts performance. I have seen almost 65hp on an engine Dyno from this change and up to 50hp on a chassis dyno.
The motor is a 1980. I don't know what block or heads it has.
I will need to dig it out of the snowbank soon to start on the motor and at that time I will see what impeller it has.

[pops1]

I have a Carlson CVX20 with a 460 and a 12JE pump with loader intake. I was told that its useless to build my motor more then 500 HP. Because the pump won't handle it do to the small intake is this true.
Will stock exhaust log handle 500 HP or more?
ThanksI would tell you that the Pump is good thru the 70MPH. Im not sure the intake is smaller. Ramp angle is different. I think insert's get a bad rap- Sure is a lot out there getting the Job Done! Not a Race Pump yet is a great OEM pump for cost efficiency and simple to the builder. Our biggest problem was shoe capability (none) some after market shoe, ride plates combo's work OK yet are still not a full force shoe, ride plate system.
Do remember the drive is pushing off the insert and transom for its forward motion. While the hard intake is a much more rigid mount and the load is on the intake- not at all on the transom. Your bottom is a far stronger, and the hard intake mount is more rigid to support the force being applied.
Most jet boat transoms are 1/4 to 3/8" as the force demand is not there. Your E pump also has the additional enclosed housing for added support.
Hope I helped.

[Lake Ape]

my cvx-20 also has a really, really tired motor in it and I am sure it runs 50 MPH at 4800 with a AA, these numbers don't add up in jetcalc. Where are all these CVX-20's coming from? My boat is very, very heavy for what it is. I need the AA to get my 230# butt out of the water!

[roostwear]

I don't know how heavy the hull of my 18' Advantage open bow is, but with a mildly built 460, tight E pump, and shoe and ride plate, it does 71 mph. I'll be tweaking the engine for a little more HP, so we'll see how it responds. It's not just HP that'll get you speed, you'll need to work on the setup to lift the hull at speed. I need a little more HP, and a G bowl with a droop would help. I have a feeling one or the other at this point wouldn't give me much more speed, but the combo should.

[Taylorman]

I don't know how heavy the hull of my 18' Advantage open bow is, but with a mildly built 460, tight E pump, and shoe and ride plate, it does 71 mph. I'll be tweaking the engine for a little more HP, so we'll see how it responds. It's not just HP that'll get you speed, you'll need to work on the setup to lift the hull at speed. I need a little more HP, and a G bowl with a droop would help. I have a feeling one or the other at this point wouldn't give me much more speed, but the combo should.
Did you notice any speed increase with your shoe? I have had other issues with my boat so im not sure about any speed increases. I did notice that it feels like it rides higher out of the water with the shoe than it did before.

[roostwear]

My seat of the pants impression is that I would have gotten the same increase from just the plate without the shoe. The RIDE is fantastic now, but I MAY have only picked up 2 mph with the shoe/plate. My hull rides fairly dry, indicating my setup is good, now I just need a few more ponies. If I add more HP, I feel I may need to drop the thrust line with a split bowl and droop to air it out more. The hull is very stable now, and I don't see it getting unstable until about 80. With more power and more speed, it may be using the loader and shoe more also. Each change I make to my setup will make how each piece works change also. Hopefully I'm on the right track.

[Liberator TJ1984]

OK, Yes those guys are on the ball at Jetboatperformance. You can look at the thrust bearing retainer and you will see a tagon the top of it. That tag is what will tell us what impeller it has unless it has been replaced. There is a bit of porting that can be done to the exhaust manifolds that will help. What year is the engine ??? Most likely the cam timing is about 4 - 8 degrees retarded, this is an emisions deel that Ford did to help burn the unburned fuel. It ends up super heating the exhaust. And it also hurts performance. I have seen almost 65hp on an engine Dyno from this change and up to 50hp on a chassis dyno.
I'm not a FORD guy but I have heard something about replacing the 460 timing chain with one from a 429 ??? to get the cam timing back advanced where it needs to be and pick up the HP #'s , since you are going to overhaul might want to research this as you will be replacing it anyways ??
good luck :D

[Jake W2]

Yea 429 chain and gears the fool proof way of doing it.
Jake

[roostwear]

Actually, the EARLY 429 set. I have a 72 429 in the roadster (what started my timing chain thread), and it is retarded (both ways), as is the 460. That's one of the things I'll be checking on the Advantage as time permits. The Cloyes set I use retards the cam timing on the CAM sprocket, not the CRANK sprocket like the factory did. I set the 460 in the boat "straight up", but if the set was retarded on the cam sprocket, I have more HP in there.

[Jake W2]

Roost I thought we went through this befor there is only A Early 429 that would make a 429 of any kind the fool proof way put it on the exact way it came off. Where the hell is that thread any way?
Jake

[Squirtin Thunder]

It looks like I opened up a can of worms !!! :wink:

[Jake W2]

What I mean by fool proof is a guy (Me) not knowing much about putting a motor togeather could take off the timing cover turn the dots on the gears till they line up take off the 460 gears and chain and put the 429 double chain and gears on bam done nothing to figure out.
I did this to mine years ago in my driveway while the motor was in the boat(a 76 Sidewinder) with a GM mec watching over my sholder I all so put in a comp cam lifters and push rods and never as much as seen this type of stuff befor.Motor still runs fine and with alot more pep.
Now When I rebuild this motor for more hp I will use a gear drive instead of the chain.
Jake

[Squirtin Thunder]

What I mean by fool proof is a guy (Me) not knowing much about putting a motor togeather could take off the timing cover turn the dots on the gears till they line up take off the 460 gears and chain and put the 429 double chain and gears on bam done nothing to figure out.
I did this to mine years ago in my driveway while the motor was in the boat(a 76 Sidewinder) with a GM mec watching over my sholder I all so put in a comp cam lifters and push rods and never as much as seen this type of stuff befor.Motor still runs fine and with alot more pep.
Now When I rebuild this motor for more hp I will use a gear drive instead of the chain.
Jake
I would not do that. The harmonics and vibration will kill the engine. Or shorten its life as a lake boat engine.
Jim

[Jake W2]

What part?I assume you mean the Gear drive.
If you mean the switch from 460 TC to a 429 TC ,it has been a few years since I did it I can not rember the exact procedure.
Jake

[Squirtcha?]

I would not do that. The harmonics and vibration will kill the engine. Or shorten its life as a lake boat engine.
Jim
This aint the first time I've heard this. I had considered going to a gear drive, but after doing lots of reading................I went with the Cloyes double roller instead. Why take a chance when you know the double roller setup works great. I've also heard that there's some machining that needs to be done on the gear drive setup to get the proper clearances (it'll rub otherwise).
There are probably a few guys here that run the gear drive, but I believe there are lots more that opt for the double roller chain setup.

[roostwear]

Roost I thought we went through this befor there is only A Early 429 that would make a 429 of any kind the fool proof way put it on the exact way it came off. Where the hell is that thread any way?
Jake
What I meant is that when you look at the listings fr a set, it typically says 68-70 429-460, 71-up 429-460. The tricky part is realizing that the one you want (regardless whether it's 429 or 460) is the early set. You can set up a 3 index late set straight up, but you just have to know wtf is going on first.

[Squirtin Thunder]

This aint the first time I've heard this. I had considered going to a gear drive, but after doing lots of reading................I went with the Cloyes double roller instead. Why take a chance when you know the double roller setup works great. I've also heard that there's some machining that needs to be done on the gear drive setup to get the proper clearances (it'll rub otherwise).
There are probably a few guys here that run the gear drive, but I believe there are lots more that opt for the double roller chain setup.
Jake
Yes I was
Talk to;
Doug Eagle
HoffmanEagleMarine@comcast.net
Shop 916.645.7003/Cell 916.257.2740
www.HoffmanEagleMarine.com
He runs them on his BBFs

[CVX20Dustin]

my cvx-20 also has a really, really tired motor in it and I am sure it runs 50 MPH at 4800 with a AA, these numbers don't add up in jetcalc. Where are all these CVX-20's coming from? My boat is very, very heavy for what it is. I need the AA to get my 230# butt out of the water!
Lake Ape, Doe's you'r boat porpos At full speed. I had to put long bolts in my ride plate and lower it about a 1 below my hull to get it to quit.

[CVX20Dustin]

What doe's the shoe do and how can it help.
My boat has a stock adjustable ride plate are these after market onces better. Will this help porposing. Thanks

[Jake W2]

Gezz I could only get on hear through my mail.
Roost I see.
Jim thanks for the info.
Dan so what do you think the best brand of doub 429 timing chain is ?I am running a doub 429 from a parts store I dont even rember the name of it?But its not a parts master I do know that.
Jake

[Squirtcha?]

Dan so what do you think the best brand of doub 429 timing chain is ?I am running a doub 429 from a parts store I dont even rember the name of it?But its not a parts master I do know that.
Jake
I haven't seen enough of the other types to know Jake. Paul (Lakes Only) might have an opinion. He seems to really follow all the BBF stuff.

[Squirtin Thunder]

I always run Cloyes.

[SB]

Lakeape, you are turning 4300 rpm.