Cam input etc...

[cudaz101]

Would like some advice on cam and other perf. parts. The boat has through transom exh. w/the snail manifolds. Mallory elec. ignition.
Cam Spec for Mild 460ci w/stock berkley JE pump.
Prefered intake manifold for all around use?? Using a Edelbrock 650 carb. Prolly need to go bigger???
Gear Drive timing assembly?? Good idea or not??
Any specific build advice would be appreciated.
Thanks in advance.
Brad

[SmokinLowriderSS]

Mild 460, cam, something like mine would work really well I think, .565" lift, 232*(50-thou, 280* seat) duration hydraulic would fit the bill quite well. It works fabulously in my working lake-boat 454. Mine is a custom grind tho to boost the ramp rates as much as possible.
Best gen-purpose manifold lake-jet-boat-wise is IMO the Edelbrock Performer RPM, I have the Air Gap version.
Some folks will tell you that you need an 850 on a jet-boat, I respectfully disagree. IMO the best size for that setup is a 700-750 CFM size. For better mileage, the Ed's would be fine, as well as a spread-bore holley (4160 style).
For maximum performance, go square-bore with a 4150 mechanical seccondary, but it will use more gas.
Timing drive, How much noise do you want to listen to? A good-quality double-roll true roller chain set is only likely to last you 2 decades or so, for $100.
Build advice, set all the bearing and ring clearances arround mid-point of the factory spec range, or just a touch wider than mid-point. You will never work an engine harder than you are about to, and it CAN be built "too tight" and destroy itself in short order, especially lower end bearings.
Don't go overboard thinking huge port heads are better, they are likely to NOT BE for your aplication.
400 HP will only spin a well-fed Berk "A" impeller to 5,000 RPM, IF you have that 400 HP at 5-grand or sooner. 700HP at 7-grand is worth absolutely squat if you can't produce enough muscle lower down to get past 4-grand.
A good set of thru-transom headers (water jacketed) CAN yield as much as 50HP, and WILL cost between $1800 and $3700 NEW (brand and material). Mine did, I gained 200 RPM but the rest of the motor build was being choked by the logs.

[cudaz101]

Thanks ALOT for your input.
I am not trying to build a monster really but 70mph would be nice. What level ov pump work would I have to do?? Or is the JE even capable??
After shoppin around it seems a SCAT or EAGLE rotating assembly 502 kit is priced pretty well w/H-beam rods etc....Would this be overkill?? I would really like some solid reliable internals and don't mind payin' up. I know I said MILD, but in terms of reliability I guess.
The price on them headers is pretty staggering...
Thanks
Brad

[Jetaholic]

Would like some advice on cam and other perf. parts. The boat has through transom exh. w/the snail manifolds. Mallory elec. ignition.
Cam Spec for Mild 460ci w/stock berkley JE pump.
Prefered intake manifold for all around use?? Using a Edelbrock 650 carb. Prolly need to go bigger???
Gear Drive timing assembly?? Good idea or not??
Any specific build advice would be appreciated.
Thanks in advance.
Brad
As far as carb size...if you want to get technical that's all governed by the cam.
The cam determines the "personality" of the engine. How it reacts, feels, etc etc. The most important thing it controls is the engine vaccuum, or how much air it draws in at a given RPM. This will determine your jet size...if your engine is drawing more air than the carburetor can supply fuel, the engine will run lean (more air than fuel), which will make the combustion chamber temp a lot hotter, which will make the engine run hot, burn pistons, valves, etc etc...which obviously isn't a good thing.
With that size motor, I wouldn't go any smaller than a 750cfm carb...most likely you will have to change the stock jet size for the proper cruize fuel mixture (notice I say "cruise" fuel mixture, which is something totally different from "idle" fuel mixture)...which you will have to read your spark plugs to determine whether or not you are getting the proper fuel mixture. When in doubt always err on the side of a rich fuel mixture. You'll burn more gas, but the motor will at least run cool and not burn things up.
As far as gear drive...well, do you want the motor to sound like it has a blower? A very common misconception is that a lot of guys will say "I'm running so much horsepower I'll need a gear drive because I'll break a chain." Well a lot of super high HP motors believe it or not run a cog belt drive...so if that were true, we would've done away with belt and chain drives in high HP motors long ago.
However, a downside to gear drive is that any and all vibrations in the crank will get transferred to the camshaft, which will transfer such vibrations to the entire valve train. Unlike with a chain or a belt.
Hope this helps.

[SmokinLowriderSS]

Thanks ALOT for your input.
I am not trying to build a monster really but 70mph would be nice. What level ov pump work would I have to do?? Or is the JE even capable??
After shoppin around it seems a SCAT or EAGLE rotating assembly 502 kit is priced pretty well w/H-beam rods etc....Would this be overkill?? I would really like some solid reliable internals and don't mind payin' up. I know I said MILD, but in terms of reliability I guess.
The price on them headers is pretty staggering...
Thanks
Brad
The "E" is as capable as a C, G, J, sorta.
You need a diverter, IMO the A-#1 most important "accessory" for a jet drive. It allows you to controll boat ride and hull attitude, both cruising, and lifting it to air it out at full-honk for best speed. Even the factory "F" pump diverter is better than a straight pump. A split bowl (sometimes cheaply found used) will give you a lot of adjustability/tunability you don't have with an "E" bowl.
A ride-plate is also needed with a diverter, it acts as a "stop" to controll the hull ride angle at full power with full diverter lift.
Add a stuffer to the pump as well, relatively inexpensive, and may be worth a mph or 2 top end.
The 460 with the right parts could fairly easilly make betwen 500 and 600 HP, below 6-grand, with very strong torque production lower, with the right combination of parts and either ported factory heads or (better way IMO, good aftermarket heads. From helping a buddy plan a 460, I like the Trick Flow 429/460 street heads, bare, so he can purchase his own prefered valve train, to get the exact pieces he wants.
I doubt anybody on here knows Fords like Lakes Only does, LO knows his shiattt, period.
That said, a 502 stroker kit is NOT overkill, but IMO H-beam rods, and (for this aplication) the forged crank over the damn strong cast Ford one is overkill.
IMO the forged crank is a 6,000RPM/600+HP need, the H-beam super-rods, the same or very similar. They WOULD be rock-solid, adn that is not a bad way to build the engine.
One of the signature lines here says something to the effect of:
"Fast, Reliable, Cheap, you can have any 2."
I agree, but you can also waste money on overkill.
PLAN FOR THE FUTURE CUDAZ. Morehorsepoweritis is a disease for which I have only seen treatment, not a cure it seems. Build the bottom end once, with room for the top end finished product, and incremental improvements become a bolt-on without sleepless nights or boatless summer days.
On a 502 I will revise my carb to 750 min, to 800CFM as best sizing, 850 no longer being so over-large.
The less-expensive Lightning Headers are Steel outer tubes, Stainless Steel inner tubes.
The super-spendy ones from various makers are Stainless Steel the whole way.
IMO, you better stay away from OT headers, the way noise regs are going. They just passed an 86db law here in Kansas and it has a LOT of the big-boat people messing their shorts right now, not me. My 4" outlets are under water at idle, I'll be lucky to reach 70db at idle at 50'.

[ck7684]

This sounds a lot like my build, except mine is a 454. I'm keeping my log manifolds for now mostly because I cant fit headers underneath my engine cover. This info relates to me too
Not sure what your boat is, but mine is a 16' Cobrajet and would do 70mph stock. My friend has an 18' Galstron Carlson with a 460 that does 55mph. Not sure if that helps you out at all, but it sounds like we are both asking the same questions and such...

[pw_Tony]

Mild 460, cam, something like mine would work really well I think, .565" lift, 232*(50-thou, 280* seat) duration hydraulic would fit the bill quite well. It works fabulously in my working lake-boat 454. Mine is a custom grind tho to boost the ramp rates as much as possible.
Best gen-purpose manifold lake-jet-boat-wise is IMO the Edelbrock Performer RPM, I have the Air Gap version.
Some folks will tell you that you need an 850 on a jet-boat, I respectfully disagree. IMO the best size for that setup is a 700-750 CFM size. For better mileage, the Ed's would be fine, as well as a spread-bore holley (4160 style).
For maximum performance, go square-bore with a 4150 mechanical seccondary, but it will use more gas.
Timing drive, How much noise do you want to listen to? A good-quality double-roll true roller chain set is only likely to last you 2 decades or so, for $100.
Build advice, set all the bearing and ring clearances arround mid-point of the factory spec range, or just a touch wider than mid-point. You will never work an engine harder than you are about to, and it CAN be built "too tight" and destroy itself in short order, especially lower end bearings.
Don't go overboard thinking huge port heads are better, they are likely to NOT BE for your aplication.
400 HP will only spin a well-fed Berk "A" impeller to 5,000 RPM, IF you have that 400 HP at 5-grand or sooner. 700HP at 7-grand is worth absolutely squat if you can't produce enough muscle lower down to get past 4-grand.
A good set of thru-transom headers (water jacketed) CAN yield as much as 50HP, and WILL cost between $1800 and $3700 NEW (brand and material). Mine did, I gained 200 RPM but the rest of the motor build was being choked by the logs.
I think this is a great set up that should run perfect if put in correctly. And I think Basset sells some thru-transom headers with hardware for under $1000 now...

[SmokinLowriderSS]

I think this is a great set up that should run perfect if put in correctly. And I think Basset sells some thru-transom headers with hardware for under $1000 now...
I think you are correct, but (I'll dig some tommorow/later today) I THINK they are water injected, which would make me nervous if enclosed. Sure would be good in an open engine bay tho IMO.