I finally got to flight test my Extra with the new Saito 91 today. Man... what a difference!! With 15% Coolpower, it performs very well with almost unlimited vertical. However, when I tried 30% nitro fuel, the plane became a rocket! On 15%, it turns the 14x6 APC at around 9600 RPMs, but it turns it ~10200 using the 30% fuel. Those 500-600 extra RPMs are definitely noticeable too... I climb straight up after takeoff with no problems whatsoever. Plus, I'm even running the engine on the rich side so I know even better performance is possible.

According to info I found on the web, the FA-82a produces 1.5 HP and only weighs 16.3 ounces. The 91, on the other hand, weighs 18.3 ounces and provides 1.6 HP. Furthermore, the 82a should fit under the cowl better than the 91. Although it is slightly less powerful than the 91, I suspect it would pull the Extra around very well... especially on 30% nitro. I don't regret going with the 91 though. Since it is my third engine for this airplane, I wasn't about to take any chances on power.

I can't recall what prop I ran with the 50SX, but it definitely didn't provide the power I wanted. I know a 60 2-stroke will perform similarly to the Saito 91, but I really wanted to go with a 4-stroke.