Originally Posted by Coolidge
That it puffed from one side of the engine and not the other is what got my attention.
At 2:36, that's the butterfly valve opening...and my guess would be releasing some "stuff" that coughed into the pipe while it was closed. I saw a little something come out the left side, as well.
The cars both sounded like they ran real well - I'm not all that worried about a little smoke early in their lives.