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425-470hp Small Block??

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Old 03-30-2006 | 07:42 AM
  #11  
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Default Re: 425-470hp Small Block??

standard chevy 010 block.

dart iron eagle heads 2.05 intake 1.90 exhaust w/ harland shard 1.5 ratio rockers.

TRW .100 dome piston. 9.8:1 compression

Summit stage 2 rods

Callies crank (Or Moldex) Forged crank a must!!!!!

Cam is an off the shelf Summit .450/.465

Stainless marine exhaust (Dry Pipe)

Thing made 425Hp at 5500 and 445Hp at 5800

Have 150hours on it with no problems.
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Old 03-30-2006 | 03:12 PM
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Default Re: 425-470hp Small Block??

the beauty of a smb is the availablility of cheap oem parts, get a 400 block and go from there, forget spending the cash on a a/mkt block. a 5140 cast steel crank should do you, some resized 5.7 rods with the good arp bolts from summit, herbert has inexspensive roller valve train, spend some bucks on good a/mkt heads and you should be all set.
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Old 03-30-2006 | 03:15 PM
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Default Re: 425-470hp Small Block??

i built a 383 with the parts described and twisted it 7600 rpms all day long in the mud hole in my jeep turning 44" boggers, never a problem and i was brutal on it. a forged crank is overkill for the hp level you're shooting for in a sbc.
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Old 03-30-2006 | 03:27 PM
  #14  
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Default Re: 425-470hp Small Block??

I'm not an expert, but I don't think you want a 400 block, they have siamese bores. You would need a 350 block with a 400 crank. There are lots of "kits" on the market. Just my 2 cents
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Old 03-30-2006 | 03:33 PM
  #15  
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Default Re: 425-470hp Small Block??

I agree with CIG3 on the whole pkg. The forged crank would be cheap insurance for the type of load on a marine engine.
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Old 03-30-2006 | 06:57 PM
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Default Re: 425-470hp Small Block??

how many people have ever seen a sbc with a broken crank?
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Old 03-30-2006 | 07:25 PM
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Default Re: 425-470hp Small Block??

Originally Posted by ratman
how many people have ever seen a sbc with a broken crank?
I've seen a few cracked....

Only one was cast.... the rest were forged.

None broken.
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Old 03-30-2006 | 08:13 PM
  #18  
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Default Re: 425-470hp Small Block??

theres a big diff between a stock cast crank and 5140 cast a/mkt crank, and hes only looking to make 450-500 ponies, and i doubt hes looking to rev it 8 or 10k rpms
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Old 03-30-2006 | 08:17 PM
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Default Re: 425-470hp Small Block??

Like you say (Ratman), I wouldn't use a forged one either for those power levels.

Put a BIG blower on it, nitrous, etc, then I would look at forged.

even then, I've seen stock 400 cranks with a real good radius job last a long time in some nasty nitro motors. (Non marine)
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Old 03-30-2006 | 09:13 PM
  #20  
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Default Re: 425-470hp Small Block??

ive got a neighbor of mine that has been trying to convience me to put a smaal block in my 27 mag....The guy knows his **** but my boat is heavy ........i threw my gps in his boat last year,it ran a 101 with his small block in a 18ft jet boat with some retarted internal parts and a 671 blower.....He talks so fast i can never keep up but he beats the crap out of this boat and it flat out halls ass......He works with a top fuel drag team and he is a incredible turner, if you guys want to know the specefics of the engine let me know..... ill ask him, hes not one of those guys who wont tell you his secerts,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,mikebacha@wya n.org
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