This may be helpful to all those on this thread who aren't discussing the Brillelli 60, which is what this thread is about.....
http://www.rcaerobats.net/GAS_ENGINE...0%20CC%20class
The B366GT, with a header/pipe system will be very close to the Original 366 GT all up weight I have on my data. Should rock with a good 23 x 8, probably even do pretty darn well with a 24 x 8.... my non-piped 366GT's do quite well with 17 lb birds, and turn 23 x 8's just fine.