PDA

View Full Version : jet boater from South Africa



JET BUG
06-05-2001, 08:11 AM
hello all
i am putting in a long distance call for some advice.I recently bought what in my country is called a "cona" it is a 72 model with a 455 olds and a berkeley 12jc jet and is 18 foot long in the U.S i think you call them "tahiti`s". The problem is that it is very difficult and expensive to get parts for the olds motor and as i am a ford man i want to drop in a 460.I would like to hear from you guys what this mod would entail,(bellhousing,etc).Currently the boat does 100km/h (62mph)at 4000rpm the thing is,i do not know what sort of hp i need to get to the 130km/h (80mph mark).i also need info on the sort of hp absorbed by the pump in order to build the new motor so that it can reach the desired rpm,with out using gas or turbo.I don`t know if this is reachable,there is very little experise
out here on this sort of setup.
thanking you in advance
regards

spectras only
06-05-2001, 08:59 AM
Jet Bug ,Ford Motorsport has a 540cu [stroked 460] crate motor that's 500HP.It would put you in the close vicinity of 80 MPH.

montrone
06-05-2001, 01:32 PM
is your engine stock?
i to have a 455 olds bored .90 over with C heads and just from them i got an extra 100 hp, also i put in a eskay 280 degree mega cam with a torker II intake, on top of that is a edlebrock 750 cfm. HEI dis. and etc, pushing close to 425 hp all under $1,000.00.
go to ebay.com search under 455 olds and you will frind all the goodies you need for your engine.
also see if you could get the Joe Mondello's book, this book is reconmended for this engine, go to 442.com and you will get tips from these hot roders.

montrone
06-05-2001, 01:40 PM
oh,
forgot one thing, check above your timing chain cover and look on the block of your engine by distrib. look for several #'s then to the right of them look to see if you see any of these leters ending with F, F1, F2 or F3, the Mondello's web site says these are the best blocks to have for modifying and performance.
I have F.

JET BUG
06-06-2001, 10:58 PM
Originally posted by spectras only:
Jet Bug ,Ford Motorsport has a 540cu [stroked 460] crate motor that's 500HP.It would put you in the close vicinity of 80 MPH.
good morning spectras thanks for the info but to import a crate motor will cost about 100,000 rand .a 3bedroom house on a 1000 souare meter property is 170,000 so its not a viable option but any info on rebulding a 460 with the right goodies would be of great help we can get parts for the fords here at reasonabe prices
cheers
jet bug

JET BUG
06-06-2001, 11:18 PM
good morning montrone thanks for the info as far as i can tell the motor is std it has the "c" type heads havent cheked the block my oldman has the exact same boat but with the "k" type heads but i am slightly quicker at "wot"about 5km/h.we looked at rebulding the olds motors but it seems you have to do a lot more work on them to get them to pick up their heels added to that is the parts avalability. Over here it`s either ford or chevy so we are both going for fords,you know the old saying "if you want to go fast bo ford,if you want to go cheap go chevy"(just kidding).Any info you might have on impeller selection, etc would be great
cheers jet bug

montrone
06-07-2001, 10:17 AM
you are right, these 455 olds are hard to find parts to, and have to do a lot to get them to move.
so you a ford man?
far as impeller, i was told "AA" it's designed for higher RPM, this is what i have.
go to http://www.americanturbine.com/ and they have some good stuff for both of our jets, and if you should find some thing i don't please let me know.
take care and good luck,
Chris

dcraig
06-07-2001, 10:25 AM
Actually an AA impeller will make a motor turn less rpm (unless your adding substantially more torque and horespower) as it takes a bigger bite with each revolution. From top to bottom are the impellers that would turn the least to highest rpm are:
AAA
AA
A
AB
B
C
What you want to do is match the peak rpm you engine is rated to turn with the impeller that will allow the motor to turn that rpm.

montrone
06-08-2001, 08:48 AM
dcraig,
But i thought it depends on your set up. see my engine is set up for high RPM, and this is what i was told to have for impeller?
unless i was told wrong, what would you suggest?
thanks,
Chris

Joker
06-08-2001, 09:11 AM
Montrone, cpperformance.com has a pump curve sheet with horsepower vs. engine RPM. If you know how your engine dyno'd it is real easy to find the impellor you need to maximize your available horsepower

montrone
06-11-2001, 11:44 AM
thanks.

JET BUG
06-12-2001, 06:07 AM
hello joker and montrone the info from the cp performance site hit the spot.thanks for the help
cheers

montrone
06-12-2001, 10:23 AM
jet bug,
No prob.

Bubbledeck
06-12-2001, 12:10 PM
Spectras Only ..
do you have any idea what that Ford stroker costs? Someday my 460 may just up and die on me and I'm wondering if rebuilding it or buying a crate motor is the way to go. 500HP sounds like enough for me.

spectras only
06-12-2001, 01:18 PM
I talked to my buddy about the 540 stroker that they were selling from FOMOCO SV catalog a couple of years ago,and it was about 5-6000$ US.It was a complete motor from intake to pan.You could search again and find out if the price still the same.Drew Backlund from Drew Marine of Spokane is a Ford guy and he built several of these engines with great succes.You can stroke your own 460 when it gets tired and need a rebuild for a lot less than the new engine,providing you have the mechanical skills.
[This message has been edited by spectras only (edited June 12, 2001).]

Joker
06-12-2001, 02:30 PM
No sweat guys

Bubbledeck
06-12-2001, 08:01 PM
Of course I have mechanical skills! I can work a key switch on my boat and operate the pop tops on beer cans heh :-)

Bubbledeck
06-12-2001, 08:02 PM
oops! BTW, thanx for the info spectra :-)

jet496
06-12-2001, 08:59 PM
Question regardin the impeller size & rpm:
I have the new 496 HO awith an AA impeller does 61 mph (radar) @ 4800 rpm. I'm happy with all that, just curious what the 496 max rpm rating is. Still havn't found much info on this motor. Had a B impeller with a loader prop on & it hit high rpm's quick out of the hole causing it to cut out on the rev limiter (I heard Marine Power disabled the rev limiter-I actually think it's a pretty good safe guard if it doesn't affect performance or fun, which it was with the B impeller). The boat builder quickly replaced with the AA (as you know the 496 is new & still has alot of figuring out to do). I'd think the A impeller would be optimal but I'm not going to change since I'm happy with what I have (pulls a skiier out of the hole great). Might gain a mph or two with the A.

spectras only
06-12-2001, 09:26 PM
Bubbledeck,here's the scoop;460 "cobrajet"535 HP SVO longblock#M-6007-C460. 535HP at6250RPM ,530 ft/lbs at4750RPM with 850 CFMcarb =5495$US retail. 514 CU.IN SVO "600HP"longblock#M-6007-A514. 600HP at 6250RPM, 590 ft/lbs at4750RPM, 9.8:1 comp.Heavy duty marine conn rods M-6200-A514 with ARP bolts,TRW forged pistons w/floating pins.Mech roller lifter camshaft,647" lift,254 degrees intake and 258exh duration@0.50lobe lift.M-6049-C429"CobraJet"aluminumcyl heads.M-9424-H429 "Victor Jr" single plane intake [requires Dominator carb]1:73 ratio alu roller rockers. 6495$ US retail. It may sound like a lot of money,but it's a brand new engine, not a rebuilt! This was two years ago.
[This message has been edited by spectras only (edited June 12, 2001).]

dcraig
06-13-2001, 08:37 AM
If your looking for efficiency, gas mileage, and engine longevity stay with the AA. An A would probably increase your top end RPM by about 150 to 200 rpm. However, that depends on what your horsepower torque peak is relative to RPM. With that motor I wouldn't go smaller than an A in a stock configuration.

Bubbledeck
06-13-2001, 09:02 PM
spectras only thanx for the Ford info ..
those Ford Motorsports motors sound good, but it looks like I'll be rebuilding the one I have when the time comes. Those are a little pricey for me :-)

JET BUG
06-14-2001, 08:00 AM
gents whats the importance of a intake/loader grate. This is some thing i have read about in this fourum ,where do you get info on what they do ,how they work etc.Does any one know of a site that gives drawings,dimensions etc you guys dont know how luky you are in the US. well thats the luck of the draw,at least you guys are kind enough to share your knowledge with jet boaters from other parts of the world.
cheers jet bug

Joker
06-14-2001, 08:11 AM
Hey jetbug,
Check out cpperformance.com inside online catalog then jetdrives and look for intake/loader grates.......lots of good info. The loader grate I beleive is to force more water into your intake which will help load your impellor and decrease cavitation in these monster bowties....Not sure how it would work out up here with all the shale and rock.....might end up at the bottom with the fishes

Slick
10-02-2001, 04:38 PM
This one has a little info on it.