Hammer Time
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From: houston
Hammer Time
I posted the question about boring out a 390 block to 428 size and this is what I found. The block was a 360 casting #C6AE-A that was in a `68 F100.The previous owner had it bored out and put CJ crank,rods,pisstons,heads and intake on it. Once I pulled it and tore it down I noticed a crack below the lifter holes on the inside water jacket.After asking around I decided that the block was scrap. I was curious about the cylinder wall thicknes,so I got the big hammer out and busted the block by the crack and you could see the differences between the fresh break and the crack. The cracked portion had rust all the way through. Then I hit the cylinder wall and it caved in like a beer can,I measured the thicknes of some pieces with a digital caliper and it came out to .130 which looked pretty thin to withstand any distortion. I think the next project will be just .030 over.
FE "Freakin Expensive"
Joined: Dec 2003
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From: Smith Mountain Lake, VA
Well had the block not been junk and the .130" wasnt on the thrust side of the cylinder wall it should have been fine to run.. I know guys that use the rule of thumb of not less than .100" as long as it NOT on the thrust Side wall...
But I have seen guys take the non thrust side down to a low as .080" and still get away with it.. How I dont know ? but they do....to thin for My money and blood!! LOL
And you want to stay even thicker for any kind of stroker build.. If ya plan on beating on it a bit!!
~Russ
But I have seen guys take the non thrust side down to a low as .080" and still get away with it.. How I dont know ? but they do....to thin for My money and blood!! LOL
And you want to stay even thicker for any kind of stroker build.. If ya plan on beating on it a bit!!
~Russ
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From: Klamath Falls OR
I posted the question about boring out a 390 block to 428 size and this is what I found. The block was a 360 casting #C6AE-A that was in a `68 F100.The previous owner had it bored out and put CJ crank,rods,pisstons,heads and intake on it. Once I pulled it and tore it down I noticed a crack below the lifter holes on the inside water jacket.After asking around I decided that the block was scrap. I was curious about the cylinder wall thicknes,so I got the big hammer out and busted the block by the crack and you could see the differences between the fresh break and the crack. The cracked portion had rust all the way through. Then I hit the cylinder wall and it caved in like a beer can,I measured the thicknes of some pieces with a digital caliper and it came out to .130 which looked pretty thin to withstand any distortion. I think the next project will be just .030 over.
Best way to check thickness is to sonic check the block! Calipers don't cut it. Also the top and bottom of the cylinders are clover shaped. Look up the Poor Mans 427 and you will see why I'm saying this to ya! JMHO Not trying to hammer you....Just giving ya some straight facts.
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