This brings back memories - around 1978 somewhere. I had 3 Barnstormers and 2 Bi Stormers. I fitted them Webra 61 Speed engines and they were "funtastic" to fly. Unless you re-inforce them to fit larger engines as you plan, they may suffer structural damage, especially top wing coming of. Need to pay attention to the cabane struts and how they are anchored to the fuse.It happened to one of mine, sending it through a kitchen roof.

But they are best flown slowly and gracefully, makes tremendous touch and go landings - good for camera planes too.

Flying pastor, If you are looking for a classic look plane with very lively performance, look ata Miss Liberty Sport or Acrobolt Sport. Both Bipes are distant forerunners along the lines of the Pitts Special. The Miss liberty probably more classic looking.