http://img130.imageshack.us/img130/6356/klipovi1qz5.jpg ok, let hear it, which one is from what engine , we got a little bit off a confusion, more about that later.... thx.
first one is a high compression piston, the other low. i'm not sure what motor they came from. if i had to guess i would say the first is a GE and the second a FE
the piston on the left is a hi-comp piston and looks 100% identical to the 4a-ge setup found in the Geo Prizm GSI and the early 90's corollas. the piston on the right is obviously a low-comp piston, and resembles a 4a-gze piston, with its dished center structure and tiny valve reliefs. if i'm not mistaken, both should be full floating wrist pin type pistons with snap rings that hold the wrist pins in place. only the early (3-rib style block) 4age used the press fit wrist pins, that were not full floating. those engines were discontinued in the USDM in 1986. 1987 saw the absolute last few press fit 4a-ge's (VERY FEW at that), and a huge influx of the full floating style. the full floating style also had larger wrist pins (20mm vs 18mm), and larger con-rod journals (42mm vs 40mm). heh... i dont know much about the 3sge, but i know a decent amount about the 4age. then again, i only have 4 in my side yard... plus 1 in my mr2, and 1 in my wife's mr2...
