ORIGINAL: broke_n_bummin
I run 11-5's on all my .40's. You lose a little speed, but it'll have your superstar off the ground in less than half the distance of a 10-6, and you'll have that extra little umph you need to pull it out of a tight spot, and ii'll idle a bit better. You can also pull the baffle out of the exhaust and still keep enough pressure in your fuel tank. I use Byrons 10%nitro 16% oil.
I largely agree -- except that this is an LA that's being discussed. It will fly around just fine on an 11-5 but it is a bit over-propped. An 11-4 will give even better performance with that plane/engine combo. It won't lose much speed, but it will get all of the take-off & climb performance that engine can deliver to the Superstar airframe.