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Discussion Starter #1
I'm looking for a build sheet that is for either a 468 or 496. I'm looking to make 600-650 reliable HP on pump gas. This will be for a 72 Kona lake boat. If anyone has a build sheet that they would like to share I would greatly appreciate it.
 

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"BEER BUDGET RACING"
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I'm looking for a build sheet that is for either a 468 or 496. I'm looking to make 600-650 reliable HP on pump gas. This will be for a 72 Kona lake boat. If anyone has a build sheet that they would like to share I would greatly appreciate it.

I have the one for my 489 that was in my baja a few years back. Dont think it made 600hp but it ran well. Wildhair has the one for his 496 he could probably hook you up with.
 

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That is a pertty big jump 468 to 496! I have builds of both you can PM me with what you need to know!
 

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I'm looking for a build sheet that is for either a 468 or 496. I'm looking to make 600-650 reliable HP on pump gas. This will be for a 72 Kona lake boat. If anyone has a build sheet that they would like to share I would greatly appreciate it.
Either CID can make that kind of power. The 496 is going to make it at a lower rpm. Lower rpm less maintenance.
 

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Either CID can make that kind of power. The 496 is going to make it at a lower rpm. Lower rpm less maintenance.


:yes: x2


Same bore and if you have to buy a crank go ahead and get the 4.250 ... 496 is the way to go IMO :thumb:
 

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Bostick Racing Engines
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I would have to ask, "What are you starting with?" i.e. what heads, crank, etc... do you have to work with. And "What sort of budget range do you have to work with?" I mean if you have tiny ovals and 400 bucks... then that will be a tall order.


You can get 600 out of a 468 on pump gas with worked up 049 ovals at about 6000-6300 fairly easy.
 

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Discussion Starter #8
I would have to ask, "What are you starting with?" i.e. what heads, crank, etc... do you have to work with. And "What sort of budget range do you have to work with?" I mean if you have tiny ovals and 400 bucks... then that will be a tall order.


You can get 600 out of a 468 on pump gas with worked up 049 ovals at about 6000-6300 fairly easy.

I don't have any parts on the shelf yet. I was kicking around a few ideas on different bore and stroke combos.
Right now I'm leaning towards a Dart block as a foundation to work off. This should give me plenty of options for bore size and if I go the stroker route I will have even more options in the future. Other than that I am open to any and all suggestions.
As far as budget goes lets just keep in in the Budweiser range. I'll gladly pay for quality and dependability.
 

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just a ski boat with bark
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I don't have any parts on the shelf yet. I was kicking around a few ideas on different bore and stroke combos.
Right now I'm leaning towards a Dart block as a foundation to work off. This should give me plenty of options for bore size and if I go the stroker route I will have even more options in the future. Other than that I am open to any and all suggestions.
As far as budget goes lets just keep in in the Budweiser range. I'll gladly pay for quality and dependability.
Well if you're talking about a Dart block and buying a crank then you might as well get the 4.5" bore (or larger) and a 4.25" stroke crank and there's 540cid or take the bore up to a 4.56 and have a 555. This can be done with the standard deck block and if you're buying all new you could go with the 10.2" tall deck and run a 4.375" or 4.5" stroke, 572 or 588 with a 4.56" bore. Just remember big engines need good heads to feed them.
 

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Well if you're talking about a Dart block and buying a crank then you might as well get the 4.5" bore (or larger) and a 4.25" stroke crank and there's 540cid or take the bore up to a 4.56 and have a 555. This can be done with the standard deck block and if you're buying all new you could go with the 10.2" tall deck and run a 4.375" or 4.5" stroke, 572 or 588 with a 4.56" bore. Just remember big engines need good heads to feed them.

X 10 If you are going to get a Dart block go with the 540 and you can stay on the mild side and have more than you asked for EASY! IMO! I would not buy a short deck small bore Dart block (unless it was a special build) it seems to be kind of backassards! As I said JMO!
 

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Bostick Racing Engines
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I don't have any parts on the shelf yet. I was kicking around a few ideas on different bore and stroke combos.
Right now I'm leaning towards a Dart block as a foundation to work off. This should give me plenty of options for bore size and if I go the stroker route I will have even more options in the future. Other than that I am open to any and all suggestions.
As far as budget goes lets just keep in in the Budweiser range. I'll gladly pay for quality and dependability.
Well... to attain your goal of pump gas 600-650hp... you really do not need to go much beyond a decent set of iron gm heads (049 ovals) and gm 4bolt block and just outfit with nice parts (rotating assembly, valvetrain,etc...) and a good amount of lovin'... especially on the heads... whether it be a 468 or 496.

But if you're willing to go Dart block and aftermarket heads then the cost would be about the same if you went anywhere from a 489 to 555. I mean the block doesn't care what you stick in it... the cost of the rods and cran will roughly be the same, as well as the pistons. You could easily attain 700 hp with a larger inch pump gas mill. The deciding factor here is just what direction would you like to go? I always have three questions I like to ask to figure out the best way to get an idea of how to go about a build: "What are your goals with the engine? What do you have to work with? and What kind of budget do you have to work with?" (not an exact figure, just a range... 2500 to 3500... 5k to 7k... 10k to 13k... etc...) I figure if you can answer those three... you can get a really good idea of what direction to go... and then get a good recipe for that combination.
 

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Discussion Starter #12 (Edited)
OK... I think if I give some more info on what the motor will be going in and used for it might just help out a little more.
i
Boat: 72 Kona with a standard set Berk. Will be turning a A or AB Bronze imp. Heavy lake boat, 4 seats, usually occupied by me, the wife, our teen, and a cooler full of beverages.

Basic use: Tooling around the lake at an average of 2800-3500 RPM with the occasional hot pass to blow the cobwebs out of the headers. :happy:

I would like to go with a hydraulic roller (I'd be more than happy to to get a recommendation from Straub on this). Like I said earlier I'm leaning towards an aftermarket block, which will be a tall deck. I'm doing this for the future rebuildability and expanded possible combinations.

As far as heads go, I'm leaning towards iron, but investing in some AFR's, RHS's, or something along that line could be a possibility.

Crank... I'm leaning towards a good Eagle or Scat.

I'd like to keep the long block in the $7000 range if possible.

OK... I hope that will help out some. Now come on fellas... give me your thoughts!!!
:thumb:
 

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WOW! You jumped big time going to tall deck! That changes everything!

Maybe you should ask the question of what can a Kona boat handle safely!:shock:

Lets see for tall deck!
2000 block
1000 stock worked cast heads 2000+ Alu. heads
2000 rotating ass.
1000 cam and lifters
1000 rockers and girts.
1000 pan and intake
500 ign.
1000 Miscellaneous and mich. work whitch I know is short!
All of this is just put together if you have a tall deck intake and dizzy deduct that! If you do any bling bling add that in the mix!
9500 with cast heads Alu. will put you over in the 10500 + range! This is new parts and not exact pricing at all!

This is when a stock block 496 sounds real good and can be built in the range you are asking for! And live a very long time! Or a 468 even cheaper!
 

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The longer the stroke the the more torque the engine builds, the bigger the pistons the more pressure it adds to turnig the crank. For a jet boat i would say as big as your wallet will let you build. For about 7g's you can build anything from 509-598 cid and still have room for a couple of rebuilds. Competion Products has some very good prices, but you still need a good machinist
 

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Discussion Starter #15
The longer the stroke the the more torque the engine builds, the bigger the pistons the more pressure it adds to turnig the crank. For a jet boat i would say as big as your wallet will let you build. For about 7g's you can build anything from 509-698 cid and still have room for a couple of rebuilds. Competion Products has some very good prices, but you still need a good machinist

I'm pretty sure finding a good machine shop in my area is not going to be a problem. In fact I can think of one that is a moderator on here that comes highly recommended. I've seen first hand some of the motors that he has done and they are very impressive to say the least.

Remember... I'm only looking for 600+ hp. This will not be an all out race motor. It will live 99% of its time under 4000 RPM.

As far as how much the Kona will handle... It is extremely solid to be putting it mildly.
 

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Thats the nice thing about big cid engines , with all that tourque you dont have to spin them very high to to make it. Dont worry so much about the hp, its the torque you want. All a jet is, is a moving dyno. If had a 600hp 454 you might have a bout 600-625 ftlbs of trq, but if you have a 600hp 540+, your trq would probly be in the 650-725 ftlbs. Now put a bigger impeller and tighten up the clearances and the pump is more efficient, with better fuel milage, at less rpm, and a little more speed.



no substitute for cubic inches
 

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I hope this isn't a hijack, but what do you guys mean when you say build sheet? Is it preferable to piece the parts together yourself as opposed to getting a stroker kit?
 

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Discussion Starter #20
I hope this isn't a hijack, but what do you guys mean when you say build sheet? Is it preferable to piece the parts together yourself as opposed to getting a stroker kit?
Build sheets are a listing of all parts and specs used in an engine build. It could include a stroker kit as part if the sheet but it could also specify individual parts of the rotating assembly. Different pistons specs will yeild different compression ratios for a given build.
 
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