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Discussion Starter #1
Sorry, search function wasnt working. Just picked up a 79 truck 454, just wondering, what am i getting myself into performance wise? have i picked myself a dog? How bad or good are the heads? block strength? crank, rods? is there a site or page that lists block and head codes for big chevys? Im a big ford (385 series) guy and decided to build a chevy due to parts availability and cost. The motor is going in a jeep YJ. i also have a 73 internal balance 460 rebuilt with a decent port job as my other option. Any help is appreciated as i am in way over my head with this. Thanks, JR
 

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One of the nice things about the bbc is the was very little change to the block over the years therefor a 79 454 is a perfect candidate for performance use. The block will be a 2blt main however don't let that worry you as a 2 blt main is good till 600hp or more. The crank will be cast but is also strong enough for most street builds. The heads will be the one weak area and will need replacing if you want to make some power, being a 79 the heads will most likely be the peanut ports with are rat turds so to speak. See if you can find your self some large oval ports which work very well on the street and are fairly reasonable price wise.
 

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Discussion Starter #3
kinda figured the heads would have to go. is it possible to put 4 bolt caps on the block? down the road im planning to boost this motor (think mud). What is the general rule of thumb regarding how much the crank will take? my intention is for around 475hp 8.5:1 motor, and throw the old gm 6-71 in my shop on it later. with 8-10 lbs, maybe 600-625hp? i know i wouldnt be pushing my luck with the ford, except the rods. Just trying to weigh my options at this point. thanks, JR
 

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The stock cast crank is good to about 6500rpm and 700 horsepower.I run a steel crank in a 2 bolt block with main studs and run it to 7800rpm,and make 700hp on motor and about 1000 on nitrous,I would say the stock 2 bolt caps will be fine at 650hp.Typically speaking,a GM 454 block will split down the middle betwen the crank and cam bores when the engine is run into the 1300hp range and experiances detonation.This is not related to if it has 2 or 4 bolt caps.After about 1600hp you should run an aftermarket block regardless.At least one drag radial racer is running low 8's in a 3600# car with a GM block that is bored .125" over and stroked to 511 cubes.With a 165mph trap speed,the numbers put him at about 1600hp,and that is about as much as anybody should try with a stock block.He does it because the rule book makes him run a stock block.Good luck.
 

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JR650 said:
kinda figured the heads would have to go. is it possible to put 4 bolt caps on the block? down the road im planning to boost this motor (think mud). What is the general rule of thumb regarding how much the crank will take? my intention is for around 475hp 8.5:1 motor, and throw the old gm 6-71 in my shop on it later. with 8-10 lbs, maybe 600-625hp? i know i wouldnt be pushing my luck with the ford, except the rods. Just trying to weigh my options at this point. thanks, JR
I didn't realise you were planning quite so agressive an engine how ever as super says the 2blt main block should be fine especially if you convert to studs. If you are looking for added security you could always buy aftermarket caps and have the engine machined for splayed main caps how ever this probably would be over kill. The seeing how you plan on using forced induction upgrading the crank might not be a bad idea at least to a good aftermarket cast piece.
 

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Discussion Starter #6
Did chevy ever make a factory forged crank for the 454?? 650hp blower motor is really making like 700, just losing 50 to the blower, but the crank stress is there, might be cutting it close? how strong are the factory rods?? crap? or useful. thanks, JR
 
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