Rare Dodge Dart GT? Which engine is this?

Well, that's a nice bedtime story, especially the 500hp Pontiac bit, but i'm sorry to tell you, it's no "race version/engine". And probably neither was that GTO
You’d be surprised. Haven’t seen it in person but my parents kept videos of their cars on my mother’s old camera, from what I’ve seen of them the Dart lived up to its name; dainty and quick. She used to race it against their friends as well, it could keep up with the ‘big boys.’ His GTO measured between 430-490 on the dyno and it didn’t overtake the Dart by much. Him and his buddies were into drag racing and since he’s a mechanic they were constantly working on upgrades. He ended up trading the Pontiac for a mini van... can’t say he hasn’t regretted that for the past 20 years