So same engine as current F2d?
same useless muffler?
same intake restrictor?
same 10%-20% caster rule on fuel?
Same lines?
If FAI changes the engine requirements, what happens? I would bet the exhaust exit size will shrink soon.
Good f2d guys get new engines almost every year for an 100 RPM. I have several cast offs that make great speed limit motors but won't pull like a new fora.