Tim's close, it's a 3.1L 60 degree V6. It's the engine that the Berettas came with (And 90 to 94 Cavalier Z24s). For a few years before they were GTPs the Grand Prixs were called TGPs and came with Turbo'd versions of that same 3.1 engine. I thought this would have been a better base engine to start from. And Adam, it's basically the same engine as the 2.8, which is what they came with prior to 1990, just a different stroke.