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Discussion Starter #1
Just got my block back from the machine shop yesterday and I'm a bit concerned... I took my builder my .030 forged pistons so he could bore the block to the pistons I put one of the pistons in without rings just fooling around and the skirt seems to fit pretty snug but if I brint the piston up to the top of the cylinder is has a considerable amount of movement in every direction. Don't know if this is typical or not?
 

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No, its not typical. You have to use a dial bore gauge to verify what the bores actually are and then measure each piston to determine which one is the best fit for each bore. Did he use a torqueplate when honing? What pistin to wall clearance did you specify when you dropped it off?
 

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It should feel the same, top to bottom. Taper on the walls (loose on the top, tight on the bottom) will prevent the rings from seating properly.

Do you have access to a dial bore gauge so you can check the work?
Wtf is a dial bore guage? Plasti-guage man... Get with the times :what:

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Plastigage wont work when checking piston to cylinder clearances. As soon as the piston gets shoved into the bore the plastigage would be destroyed. Use a dial bore gauge on the cylinder and a digital caliper on the piston. Some digital calipers can do both.

When checking piston to valve clearance, use a wad of playdoh. When installing a crank, then use plastigage.
 

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:lmao I was joking guys... Whenever someone around me mentions building an engine, they're like "oh yeah bro, let me know when you build it. I'll bring the plasti-gauge over and we'll assemble it" haha. Just funny to me is all.

Carry on. Listen to NX and WillyT. They have obviously done this quite a few times before ;)

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Just got my block back from the machine shop yesterday and I'm a bit concerned... I took my builder my .030 forged pistons so he could bore the block to the pistons I put one of the pistons in without rings just fooling around and the skirt seems to fit pretty snug but if I brint the piston up to the top of the cylinder is has a considerable amount of movement in every direction. Don't know if this is typical or not?
Cylinders should be perfectly straight from top to bottom. Is the shop reputable? Sounds like they had an issue with that one cylinder and figured it was close enough and that the rings would take up the slack and just honed it a bit to clean up any ridges.

Maybe it was 'the new guy'.
 

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:lmao I was joking guys... Whenever someone around me mentions building an engine, they're like "oh yeah bro, let me know when you build it. I'll bring the plasti-gauge over and we'll assemble it" haha. Just funny to me is all.
Superglue and duct tape!
 

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OK, I feel better now :lmao

Calipers will not help measuring exact piston size, they're just not accurate enough. Especially digital ones, which usually measure in .0005" increments. You'll need a good micrometer to measure skirt size.

Calipers work great for getting a quick idea of general size (STD, .010", .020", etc.) but for precise stuff, micrometers are the way to go.

You may notice I keep posting Mitutoyo stuff. They make real good instruments.
 

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Discussion Starter #12
The shop is very reputable. Maybe I didn't make it clear the cylinder is the same top n bottom the pistons are not. Most pistons are wider at the wrist pin area and skirt right?
 

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Discussion Starter #13
I say the skirt ist tight cuz it goes in first when I say the piston has slop at the top of the cylinder its the very top of the piston the skirt is snug all the way through
 
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