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Discussion Starter #1
.. so the block that I overpaid to have the machine work is toast now ($1000 to hot tank, bore .030, and line hone). My fault, I didn't know what I was doing when I honed it and I tapered the cylinders, doh!:eek: Feel free to call me an idiot, haha. (I laugh on the outside, but I'm crying on the inside, thats a lot of money wasted!) Now I have a choice, either buy a new Ford production block from Summit, or get one from a junkyard. The guy who is helping me swears that you don't have to magnaflux an old block, he has an oven and some type of cleaning machine and says that when he gets done with cleaning the block, you would be able to see any stress cracks... I thought the point of magnafluxing a block was to see cracks that you wouldn't normally see with your eyes on just a cleaned block, am I wrong?

Anyway, I want to get the block from summit because that would eliminate worries about having a crap block, but getting the one from the junkyard will save me about $400. What do you guys think?
 

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I say don't let him touch it...isn't the summit block ready to go except for the finished hone to clearnace your pistons?
 

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Discussion Starter #3
I'll have to call. I think they are, but I already have .030 pistons and I've already had my rotating assy balanced.. and I already have a custom grind cam for a 306, otherwise I would say screw it and get a 347 from woody.

I would have to get it bored regardless.. unless they have bore options at summit.

So junkyard block = bad idea with no magnaflux right?
 

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Magnafluxing will bring out the cracks that the unaided eye can not see. Your buddy is on crack. I think you should magnaflux him.
 

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^+1 Save yourself alot of grief. I did the exact same thing you did the first time around. Bought a used Sportmans block and spent $1000.00 making it "right" Down side was it had a slight twist and had to be decked .004. Cracked right up the middle that summer and bitched up another $2000 worth of forged rotating assembly stuff. Ended up buying a new Sportsman block from Summit for less than I ended up with in the first one. The production blocks and Sportsman blocks are already finish honed to 4.000. The bitch is 2 years ago Summit dumped their entire stock of 5.0 production blocks for $250.00 a piece. Next thing you know, their back at twice the price. Same thing with the Ford aluminum drive shafts. Cleared out the stock at $175.00 a shot and now they are back at twice that, at least I bought 2 of those. Good Luck
 

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You were honing this yourself?? It's not a lawnmower engine:eek::eek:
 

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Discussion Starter #7
You were honing this yourself?? It's not a lawnmower engine:eek::eek:
Haha, I know... keep em comin cause I deserve em.

The guys that I used to rent my garage from gave me the stones attached to a cordless drill and told me it was pretty hard to **** up... Yea, I'll be sure to listen to them again. Live and learn, right.
 

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Get a "ball hone". Great for breaking the glaze off of cylinder walls for low dollar re-ring jobs where the bores still meet tolerances.
 

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Discussion Starter #9
So the guy helping me was at the shop today while I was at work, and he decided to change his mind. Now he thinks that he can hone the taper out and be @ the 4.032 that the pistons I have require. But at this point I still have to figure out if my line bore on the mains is right. We checked the new crank and it is perfectly straight, so its definitely a bore problem there. He is going to measure it tomorrow and see whats going on with that and then I will be taking it to another machine shop to have them cut the caps and re-line hone it to what it should be. But that all depends on if he can hone out the taper in the cylinder walls. Is there an accepatable tolerance for cylinder taper?

..at this point, I'd rather eat my own feces than ever build another short block on my own.
 

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Maybe just buy a machined block from summit for $500?? Might be cheaper than the machine work on this block.

Anyway, can't be much taper if you can still get it under 2 thousandths. Probably will not hurt much, but why risk it?
 

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Discussion Starter #11
It all depends on the cylinder walls and how much the line bore will cost me. My guy has the equipment to hone the cylinders and he won't charge me much, if anything, to do that. If they are good, then its all down to the cost of cutting the caps and re-doing the line bore. This guy is telling me that he thinks he can get the taper (cylinder walls) to 1 thousandth difference, max, from top to bottom on each cylinder. Does that sound like thats right? I've never done this before so I'm just going by what he tells me.

The way I look at it, $500 block + $99 shipping + $120 bore = $719 vs. whatever a line hone costs, which I'm sure isn't $719. So I'm going to see what happens with mine. I have decided that I will go with the new block instead of a junkyard block, if mine is fubar'd. I should know tomorrow what I'm looking at.
 

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I think the blocks from summit come finished at 4.002 ready for pistons.
 

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2 thousandths taper and it will eat oil like no tommorrow, the tolerance for out of round and taper is .0002-.0004

thats 2-4 TEN thousandths, not thousandths

Unless you have a .0001 dial bore gauge and mic to set the gauge in, your pissing in the wind
 

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Discussion Starter #14
2 thousandths taper and it will eat oil like no tommorrow, the tolerance for out of round and taper is .0002-.0004

thats 2-4 TEN thousandths, not thousandths

Unless you have a .0001 dial bore gauge and mic to set the gauge in, your pissing in the wind
Thanks again, as always, thats the info I'm looking for. I'm going to bring this to him and if he tells me thats not needed, I'm buying that summit block and taking it somewhere else to have it done. I'm tired of this guy.
 
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