Hey,
Good job so far, in the BF1 explosion (http://www.youtubeonrepeat.com/watch/?v=9dUvAQ7HmDo&from=27&to=316) I did what @Partikel said. The quick directional elements are only a few frames and stay quick and snappy, then I spawn a different emitter with the lingering smoke.
It’s usually really hard to make one emitter do both and much easier to split them up in to two emitters (or more) so you can tweak the behavior independently.
After you nailed that I would work a bit more on the shape (it looks a bit like an upside down T right now instead of a V shape), then add more depth to the explosion with more detail like derbies and so forth.
Good luck! 