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Don't know jack about a BBC, please help

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Old 09-11-2012 | 08:53 PM
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From: Daniels, WV
Default Don't know jack about a BBC, please help

I've got a friend that's got a 330hp 454 now. He's looking to add some horses and needs some help. I'm still learning SBC and don't know jack about BBC stuff so I'm gonna ask you guys for some help. This should be a fairly simple build as we are looking to get between 450-500 horse power in the end. Here is a list of goals we have and if you guys could please chime in and let me know if this is doable or not. Please feel free to suggests parts as we go:

1. Only thing that will be reused is the block (besides ignition and accessories etc)
2. Can we get this power with iron heads or do we need aluminum? (please feel free to make suggestions on proven heads)
3. Needs to be some what mild mannered around the dock and what not
4. This is not a race boat and never will be, still gets used for tubing, skiing, partying, and cruising. Needs to have good midrange capability and good power up top for the occasional WOT run
5. He has under platform exhaust. Would prefer a cam that will work with stock style short risers (please feel free to make cam suggestions)
6. It's a 1990 model engine, is it a roller cam setup or no (if not can it be converted)
7. What size carb?
8. Single or dual plane intake? (again suggestions welcome)
9. Would a forged rotating assembly be necessary or would cast work?
10. What would be a safe and reliable rpm range for a BBC of this nature?
11. Last but not least... Can this be done for under $7000?

Sorry for the list of questions that have probably been asked 1,000 times on here, I'm just trying to keep all my info in one spot, makes it easier for me to recall it this way.

If you feel that I missed anything feel free to add info as well

Last edited by 87MagnumII; 09-11-2012 at 09:50 PM.
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Old 09-11-2012 | 09:50 PM
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Buy a complete engine, it would be cheaper than what you are talking. Seriously.
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Old 09-11-2012 | 09:52 PM
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Originally Posted by BBCLiberator
Buy a complete engine, it would be cheaper than what you are talking. Seriously.
Even if we shopped for deals on good used parts? I'm not arguing, just curious as to what it would take to build something like this
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Old 09-11-2012 | 10:12 PM
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Originally Posted by 87MagnumII
Even if we shopped for deals on good used parts? I'm not arguing, just curious as to what it would take to build something like this
To get what you are looking for and to get 500hp is going to require some money, I don't think the 90' is a roller motor either. You also state you want it to be mild mannered, so in that case you should do a stroker. Find a take out 496 or a mild 502 and save yourself the time and hassle. A good benchmark is the 454/420, really to go past that with the needs you describe, you need to do a roller conversion.

Good Manifolds
800 or 850 carb and matching dual plane intake
Run probably 5500+rpm
Rectangle port heads (or quality aluminum set of your liking)
Roller conversion as you'll need a nice cam and matching valve train to support some higher lift #'s
Crank
Rods
Pistons

I mean if you are really replacing literally everything, just buy the whole thing done already.

Either that, or really lower your horsepower goals...if you want it reliable and tame like you describe.

Even if you get deals, I'd say you have AT Least $4-5k in it, and a pile of parts that need to matched/machined/assembled/tuned/tested, and of you buy all used, probably a few surprises along the way...just my take.

THe roller conversion on my 502 ended up costing about $1500 when I had all the stuff needed to use the cam I wanted.

Last edited by BBCLiberator; 09-11-2012 at 10:20 PM.
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Old 09-11-2012 | 10:22 PM
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Originally Posted by BBCLiberator
To get what you are looking for and to get 500hp is going to require some money, I don't think the 90' is a roller motor either. You also state you want it to be mild mannered, so in that case you should do a stroker. Find a take out 496 or a mild 502 and save yourself the time and hassle. A good benchmark is the 454/420, really to go past that with the needs you describe, you need to do a roller conversion.

Good Manifolds
800 or 850 carb and matching dual plane intake
Run probably 5500+rpm
Rectangle port heads (or quality aluminum set of your liking)
Roller conversion as you'll need a nice cam and matching valve train to support some higher lift #'s
Crank
Rods
Pistons

I mean if you are really replacing literally everything, just buy the whole thing done already.

Either that, or really lower your horsepower goals...if you want it reliable and tame like you describe.

I figured it would be a little easier to get 1 horse power per cubic inch on a 454. Shows what I know
Glad I asked, I believe we will start shopping the "already assembled" isle at the engine store
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Old 09-11-2012 | 10:26 PM
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dave,i recomend finding a used hp500 and rebuilding it,they are iron head motors,8.75 to 1 compression,and hyd roller cams,and idle around the dock all day long,just my thinking.
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Old 09-11-2012 | 10:31 PM
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Originally Posted by mike tkach
dave,i recomend finding a used hp500 and rebuilding it,they are iron head motors,8.75 to 1 compression,and hyd roller cams,and idle around the dock all day long,just my thinking.
Already hunting. What kind of hours can you put on these before they need a rebuild?
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Old 09-11-2012 | 10:35 PM
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From: OFallon,Mo.
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[QUOTE=87MagnumII;3774878]



Yes it could certainly be done for under 7K.
5200 rpm
Forged crank and pistons
Dual plane Edelbrock RPM air gap
750 holley or edelbrock carb
1990 should be a Mark IV so no roller.Can be converted.About $1200 to set up a roller(Cam-Lifters-Springs-Pushrods)
Could work with the right iron heads.
Exhaust is going to be your problem. For the power you will be limited to with that exhaust you may as well keep it stock.
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Old 09-11-2012 | 10:36 PM
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Originally Posted by mike tkach
dave,i recomend finding a used hp500 and rebuilding it,they are iron head motors,8.75 to 1 compression,and hyd roller cams,and idle around the dock all day long,just my thinking.
I agree 100%. Re-reading this I really sound like a downer, so let me say this, can it be done, absolutely. However, I've seen so many people dunk more money in a 454/330 and almost always I think to myself, you could have had <something way nicer than they ended up with> for that. If your goal was 380-400hp it's a totally different conversation.
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Old 09-11-2012 | 10:46 PM
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Originally Posted by 87MagnumII
Already hunting. What kind of hours can you put on these before they need a rebuild?
This is a loaded question, huge variety of answers here, some will tell you a million, reality is, if you get one with more than 250 hours on it you should just go through it. Everyone can chime in and tell me I'm nuts now

I just went through the top half of my motor and replaced the springs etc. since I'm hoping to get 500 hours out of it before I rebuild completely. Some may call that overkill, I call it cheap insurance...
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