At room temperature, our Sunnen press fixture shows 1500 PSI-2000 PSI typically to get the pin to begin moving. Then it rapidly drops to around 1000 PSI as the pin pushes out. The actual press we shoot for size wise is .0012"-.0015" press fit. Over .002", very hard to install without overheating the rod small end. Under .0008", it is likely the pin will migrate out of the rod, especially if run hard. We all know what that results in. Ford FE engines are a particular problem from what we have seen at the school. Had a 390 where the pin rode on a cylinder wall for so long, it finally cut a groove completely through the cylinder wall into a water jacket!! Incredible.
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