This page will focus on the engine block details themselves

All series 2 and series 3 engines share the exact same block. The only real difference is the stamping on the blocks. It doesn't matter if the engine was supercharged, naturally aspirated, or if it was in an f-body car. You can use any heads or any external parts you'd like to on any block.

The only differences are within the engine internals.

You can identify any 3800 block based on a ID casted onto the block itself

3800 Engine VIN number? - Pennock's Fiero Forum