Deck height

[Globedog12]

New aa pistons and cylinders
2.0 94mm bore cylinders.

Started mocking up cylinders to figure cylinder base shims. I used a dial indicator to find tdc. I started with the number one cylinder. With no base shims I’m finding deck height differs .004 from one side of the piston to the other. I’m measuring above the pin on each side. One side is .009 the other is .005. I get the same measurements using depth mic and feeler gauges. Is this enough to worry about? In the next day or so I’ll swap out the piston with another to see if I get the same measurements. Cylinders are torqued with aluminum bar diagonal across.
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1976 VW Type 2 Original fuel injection

[SGKent]

strange. Are the cylinders held down like suggested? If not the results won't be reliable. If they are held down. Hmmmn. I have used Kolbenschmidt, and Mahle sets, and they were usually within .001. It also depends if the case is flat and not sagged in the center. I don't believe the height will matter if the cylinders are parallel to each other UNLESS the rods are twisted or bent. They are pretty robust for the displacement. I guess AA could have less tolerance than Kolbenschmidt or Mahle but it is really hard to find those now.
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"Most people don't know what they're doing, and a lot of them are really good at it." - George Carlin

[Globedog12]

I don’t think the case is sagging in the center. My larger measurement is in the middle of the case. The cyliner is torqued down. I’ll try mocking up the number 2 tomorrow to see if I get similar results.
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1976 VW Type 2 Original fuel injection

[Wildthings]

What is the surface like where the cylinders bear on the case? There is often wear in this area

[Globedog12]

[airschooled]

Flip the rod over and remeasure to make sure the rod is not bent… Same with the cylinder to make sure the head/measuring surface isn’t out of plane. I think the case deck is more likely at fault though…

Robbie
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[SGKent]

without a rod jig, an easy way to check the rod is you have 4 connecting rods. You tighten the big end enough to hold it together, making sure that the halves are aligned. Put a wrist pin into the small end. Set the second rod onto the wrist min and check the big ends to make sure they sit parallel. Some rods will not allow the big ends to touch but I think on ours they do. Then flip one rod over and check again. If there is a difference. grab another rod and check against that. The wrist pin will be straight.

You can also put a piece of tape on the piston in question and tell yourself to change it - because you can flip it the wrong direction and see if the high side migrates. You can check another barrel and piston on the same cylinder position and see it it has the same difference. When done if you flip it, flip it back and take the reminder tape off.
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"Most people don't know what they're doing, and a lot of them are really good at it." - George Carlin