RE: Engine for Goldberg ultimate
The Saito, will give you great performance and likely scale performace.
Mine lands tailwheel first. Aerobatics do not require a great amount of speed.
Knife edge loop will require a little more power.
I swaped to the YS 1.20 with a Graupner 14x7 3 blade and it's just right.
this was the older YS ...non- air chamber.