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I currently just got my block my cylinder head and crank back from the machine shop a while back the cylinder walls were wore 0.010 thousandths of an inch........so we bored it 0.020 over and then the block was honed. They also had to deck the block surface.......and mill the cylinder head 0.016 thousand ths of an inch. Me and my grandpa ordered the piston and rod and rings after we had it in the machine shop. A lot of local pullers say the recommend that specific machine shop. But the question is was it the wrong way of doing the steps. The parts supplier said I should have ordered the piston first to have it taken to the machine shop and bored to fit it. Should I worry about this.
 

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It could be a problem. I am surprised the machine shop bored the block without the piston for reference. It all needs to be measured and then you will know the situation. If the bore is too large a .030 oversize piston and rings would be needed and rehone the bore to the correct diameter. Let's hope it is slightly undersize or within specs. Just for future reference purchase the parts first then go to the machine shop and everything can be properly fitted. Good luck.
 

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I have always been told to have the machine work done first then buy the parts that way you get the right part. So you didnt do anything wrong as long as you buy .20 over piston and rings you will be ok, our parts supplier never tells us to buy the parts first they make the parts that we order are correct for the block but they are a really nice parts dealer that will get you the right parts the first time so you dont have to come back and all the machine shops around here will not touch the parts for the motor you just have them do the machine work and you install the parts that way if something go's wrong they are not help accountable. so I will say you are ok you should be all set to put the motor back together.
 

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There seems to be different opinions on this as I expected. After consulting with my friend who owns an engine machine shop he says it can be done both ways. If the block is bored first the machine shop has to kknow the stock bore so to have a" finished" dimension. He also said that an engine machine shop will prefer to have the parts on hand to check the fit. Some piston and bearing makers may have different tolerances for their products so pre measurement is a good idea. He also stated that they very often do some assembly per customer request. I guess it all comes down to how your machine shop is set up. But I still say you need to measure everything before starting assembly to ensure you have good fit of the piston and rings. The performance and life of the engine depend on this fitting. Let us know how it turns out.
 

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we have one place here that wants the pistons and such in had to make a perfect fit, other places dont care they just hit the general middle mark of the specs...ive done it both ways, and the buy parts first and have block made to fit seems best...
 
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