[cycleguy55]

I'm thinking you'd also need a new cam to go with the flat plane crank. Another area of deal with would be changing the ignition system to fire two cylinders simultaneously, rather than sequentially.

As far as the sound, it seems to me a Ferrari or Maserati with flat plane crank might be a good indicator of what to expect. Here's one link ([ame]https://www.youtube.com/watch?v=RLPOpgP9pEk[/ame]), but there are plenty of choices on YouTube.