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Discussion Starter · #1 ·
I just picked up a rebuilt 454 with 7000 miles on it. it has flat top pistons and 049 casting heads which =7.81 CR :( can I be in the 400 horse range with the right cam and intake? or will the low compression really hurt me.
 

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Perfect candidate for a supercharger.
 

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If you have those heads worked, have the bottom end redone and balanced, and a set of TRW forged slugs, you can make 500 hp. I did with a set of 781s. The key to these open chamber heads is a good 3 angle valve job, 2.19 / 1.88" valves, and some bowl blending. A good dual plane intake, and a not so radical cam and you are there. I can explain more if interested.
 

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Discussion Starter · #4 ·
I just want to throw a intake and cam in it I don't want to spend a lot of money. budget build bro.:rolleyes:
 

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With a 7.8:1 CR it is going to be hard to make 400 hp. I would say an easy 325 - 340, but that will be about all. Most cams are better suited for 9-10:1 CR, you would need minimal overlap to keep cylinder pressures high. Someone will speak up who has run something similar, but do not expect big numbers. At this point I would shelve the 049s, and pick up a set of peanut port heads to make low end grunt, but it will run out of steam around 5K RPMs. JMO.

Tiny
 

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Discussion Starter · #9 ·
With a 7.8:1 CR it is going to be hard to make 400 hp. I would say an easy 325 - 340, but that will be about all. Most cams are better suited for 9-10:1 CR, you would need minimal overlap to keep cylinder pressures high. Someone will speak up who has run something similar, but do not expect big numbers. At this point I would shelve the 049s, and pick up a set of peanut port heads to make low end grunt, but it will run out of steam around 5K RPMs. JMO.

Tiny
I do actually have a set of 360 casting peanut port heads.
 

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yep that sounds like the best bet. Try to get the compression up . Save the 049's for when you change pistons. The smaller the combustion chamber size the more compression you can get. Also using a thinner head gasket helps. It will sound good with the 280 in there.
 

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Personally I think the 049s will be less beneficial with the compression you have. Like was said before, the 049s have about a 118 cc chamber, which does nothing for your compression. If you were to use peanut ports with say around 100cc chambers, you would gain almost 1/2 point. This is where your power is going to come from.

Tiny
 

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Got any bb buddys with some colsed chamber heads? That will get the CR up more. I had a set laying around but gave them away a few months ago. I bet a buddy of mine has some, if you lived alittle closer I could prob help ya out but shipping on iron heads would a ton. Just hold onto the 049's if you dont run em.
 

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YUP.. When I saw the 7.81:1 thats a perfect compression for a blower. Feel lucky, many guys have to rip out pistons to drop the CR to put an air stuffer in. I would go easy though, but a small huffer will easily get you above 400HP. And where did you pick up a new engine with that CR, bet it was a nice score. JR
 

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That would be pretty sad if you can't squeeze 400 h.p. out of 454"
I could probably scrape enough small block junk off the shop floor to make 400 h.p.
 

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Discussion Starter · #17 ·
That would be pretty sad if you can't squeeze 400 h.p. out of 454"
I could probably scrape enough small block junk off the shop floor to make 400 h.p.
I know I can get a whole lot of power out of my 454 but money is an issue of course and I am hoping I can make some decent power for not a lot of money
 

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IMO the key to power is a solid short block. With the stock rotating assembly, and dished pistons, you will need heads with a small chamber. This will bump compression. Otherwise, performance heads and big cam will not make power, but they will cost you power. I went 10:1, with a hydraulic flat tappet, receonditioned the rods and crank, and a set of worked 781s and just cracked the 500 mark. So you can see where the need for a solid rotating assy is a must. If you do not have the money now, build what you can, and enjoy it for a while. Save money, then when you have more money put it into the engine. Best of luck.

Tiny
 
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