4.030 blocks and oversized pistons
#1
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I have a iron 6.0L block that was advertised as being a 4.030 bore. One would think I would have to order pistons 0.30 over After measuring cylinders (which are finished honed) I get a bore of 4.0261 to 4.0274. Is this normal or are they way off on their machining? On one hand…. the pistons I want to use GMPP 89017479 - LS-Series Piston are 0.020 oversized and if within tolerance will give me a pretty good piston to wall clearance. On the other hand… if the bore was 4.030, wouldn’t 0.030 oversized pistons not work.
I know most people finish hone to the pistons, but what do these manufactures that finish hone their blocks expect the customer to do? Any encounters welcome.
I know most people finish hone to the pistons, but what do these manufactures that finish hone their blocks expect the customer to do? Any encounters welcome.
#3
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confident on my measurements and piston selection…would use the pistons mentioned instead of taking a block to a shop…kinda makes more cents$.
#5
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thanks KCS...thats exactly the feedback i was looking for. so .020 pistons from GM are going to be around 4.016?