Is a 3.8L V6 Pontiac engine interchangeable with 3.1L Chevrolet engine?
No, a 3.8L Pontiac V6 and a 3.1L Chevrolet V6 are not interchangeable. They have different block designs, bolt patterns, and overall dimensions. Even if you could somehow overcome the block differences, the ancillary components (intake manifold, oil pan, etc.) would be completely incompatible.