Would these be acceptable

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1930

1930

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When I initially measured how far down in the bore the pistons were I installed assy but did not torque anything down cause Ive read that the rod bolts can only be stretched so many times before they become damaged.

Snugged down bolts/nuts, took my measurements and asked machinest to remove .013 off the odd side and .022 off the even side which he said he did, now Ive taken the same steps to reassemble ( just to check his work ) and these are the measurements Im getting.

Id say the even side is where he started, those measurements are pretty good, the odd side dosent look so good to me?

Would I be out of line to ask the guy to make it right?

Pistons went back in the same hole, no screwups there and everything was tightened the same way it was initially.

Safe to assume that the even side is acceptable? Hes working with very old equipment, I wasnt expecting absolute perfection but on the same token I want to get what I thought I was paying for which would have been everything close with .002 max.
 

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It's up to you. You could politely approach him about it and see what he has to say.

I wouldn't fight about it. Who was it that said this ain't NASCAR?
 
IQ52 said:
It's up to you. You could politely approach him about it and see what he has to say.

I wouldn't fight about it. Who was it that said this ain't NASCAR?
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I already know what hes gonna say and no it aint Nascar so it dosent have to be perfect but if it aint right then it aint right either so I guess Ive already made up my mind on it.
 
Well your rods, pistons, bearings and crank would all be variables that can vary. Then you need to be at 100% tdc for measurement. Are your chambers going to be as accurate?

What is your build and expectation?
 
what I did was put the 4 shortest rod/pistons on the short side of the block, and the 4 longest on the long side of the block, not racing for the world championship
 
Machinest said he would take care of it
 
1930 said:
Machinest said he would take care of it
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How? 1st, the way the image is shown we're looking from the bottom, & You've got piston heights above & below & it doesn't grade progressively one way. I'm thinking it's
your pistons that are varying, not the deckwork, granted there is the slightly tighter avg. but .002" isn't going to make a s**ts bit of difference unless you were trying to
push the envelope with a super tight squish area.
 
I assembled the crank and pistons initially, took my measurements as far as how far down the hole they were, averaged the measurements and decided on a number each side to remove from deck, disassembled engine, asked machinest to remove X from one side and X from the other to give me the zero deck height I was after.

He removed the X I asked him to remove from the odd side ( or he got it pretty close ) and then he removed whatever was removed from the even side which wasnt enough.

I reassembled engine the same way I had assembled it the first time and found the errors, took it back apart again and asked him to make it right by removing what was still needed on the even side.

Hopefully that makes sense now
 
OK, I get what You're saying, but Your first post & last post contradict each other as to which He got right. Assuming You're shooting for a zero piston to deck, then one side is
shy, I get it...but really won't make any diff. truthfully. Random/uneven carbon build-up will exceed that variation in no time, but it's cool if He's willing to set it up to tweak
the high deck to match, that's a keeper for Your business!! :thumbsup:
 
Another perspective and based on the opening post... If you really wanted it "RIGHT" you should have had the crank turned, indexed, and stroke corrected, the rods resized (so the lengths are equalized), and the block align honed, and machined on a fixture to square deck it. You used a local guy, with old equipment, and haven't touched the other variables. So no offense, given what you seem to be doing, it's fine to me.
 
From 1 1/2 above to 5 below we are talking about a TOTAL of all of 6-7 thou. This assumes you have no errors in YOUR measurements.

PUT THE DAMN THING TOGETHER.

What you might do is play musical chairs with the pistons/ rods
 
moper said:
Another perspective and based on the opening post... If you really wanted it "RIGHT" you should have had the crank turned, indexed, and stroke corrected, the rods resized (so the lengths are equalized), and the block align honed, and machined on a fixture to square deck it. You used a local guy, with old equipment, and haven't touched the other variables. So no offense, given what you seem to be doing, it's fine to me.
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Yeah I knew this after the fact, your right, Ive been doing alot of reading and I should have had these things done.

67Dart273 said:
From 1 1/2 above to 5 below we are talking about a TOTAL of all of 6-7 thou. This assumes you have no errors in YOUR measurements.

PUT THE DAMN THING TOGETHER.

What you might do is play musical chairs with the pistons/ rods
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Hes done with it, picked it up this A.M. Im gonna wait for the 340 machine work to be done and then put them both together at the same time. I believe I have most all the parts
 
I understand theres not too many things perfect but Id like to give it my best. Im gonna assy the 4 corners this Sunday and hope that its cut down correctly this time.
 
1930 said:
I understand theres not too many things perfect but Id like to give it my best. Im gonna assy the 4 corners this Sunday and hope that its cut down correctly this time.
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When you do that; I use the same piston/rod in each location first, and measure the deck-heights with it. This removes the piston and rod variable from the procedure, and limits the deck-height error to just the crank and the decks.
In my limited experience, I have found that the piston compression distances are very well controlled. But resized rods maybe not so much. And the only way to separate the long from the shorts for me, was to stick the same piston onto each rod, and drop it into one particular hole. Then record the deck-height with rod. From shortest to longest, my rods varied about .004 or .005.
Then using the same piston/rod assembly in each hole, I found the deck-heights also varied by .004 IIRC. So by not playing musical rods, the maximum error in deck-heights could have been up to .009
Since I was wanting to run a squish of .039 (the thickness of the 1008gasket), the minimum would have been into the mid/high .020s. Being a newbe my opinion was that,that would be too tight.
By playing musical parts, I was able to finalize the deck heights at .005 plus or minus .0015. So the deck-heights came in at plus .0035 to plus .0065, and minimum quench thus .0325
Had I been unlucky enough to get a long rod on a tall crank-throw, into a short hole,well...... you can see the results might have been broken parts.
In any case;
Happy Fitting!
 
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What AJ said. Pistons are accurate most of the time. But crank and rods are not.
 
Thanks, since the engine has been mocked up twice already with the same piston/rod assy in the same holes, measurements taken and assuming the appropriate material removed from the deck all should be well enough I would think without playing musical pistons.
 
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