Finally I got to talk with Steve, the guy who had it in his Challanger for two years. He bought the car on ebay from someone who didn't know anything about the engine. Steve states it ran great with no vibes and nothing weird, he said it actually ran smoother than most of the cars he has owned. He is an experienced car guy with lots of different projects in the past such as turbo and supercharged engines both for street and track so I guess we can trust what he says.

I got to check my engine closer today and there is no longer any question, it is a LA 360.

Since the flywheel Steve used was unbalanced the engine should not vibrate with an unbalanced TC but it does, so I guess something is wrong with the TC.

I was wondering because I'm planning to replace my 904 with a 46RH and I need to gather parts for the swap.