First off, I finished the model and have put 2 flights on it. It was “too” windy but I flew it anyway. A few aborted landings but I waited for a break int he wind and lands very nicely. For FYI, I balanced the model at 3.75” at the wing tips. I assembled the model and balanced before installing batteries (two A123’s), rudder servo, ignition module, optical kill, voltage regulator, pull-pull, etc. Then I moved everything around until it balanced. It was at perfect CG when completed and required no additional weight at all. Also to my great surprise, after the plane was airborne it required ZERO clicks of trim on ANY channel. I have never had this happen before on a new model. This is my first large scale/gasoline model so excuse what may be obvious. My questions are as follows and I thank you all in advance for any input you provide:

1. I am running a DL-50, the engine runs fine on the ground at all RPM ranges and tranisions fine, but seems to run less that optimum in the air. I have heard that some people put some sort of plate over the carb to prevent forced air from entering into the mixture control. Have your heard this? Is it neccesary? Would question #2 cause this?

2. Please review the attached photos, does it appear that I have sufficient clearance/air exit around the engine? Or is it too tight?

3. I am using ball links for the throttle. This seems to transfer a lot of vibration to the throttle servo. At full RPM I can see the rod vibrate substantially, and if I touch it, I can feel a lot of vibration being transfered. Should I be using something less rigid? Should I be using ny-rod and standard clevises with a little more “slop” to release some of this energy? I balanced the prop and hub both. (see hardware photo of the throttle servo)

4. Should the wiring be tightly secured or left somewhat loose when “zip-tied”? (see photo of my receiver)

5. Question on the cowling: It was extremly difficult and time consuming to install the two screws for the lower cowling (from inside of the cowl to the firewall) with the engine/muffler installed. Given the "hook" type mechanism at the bottom, are these screws necessary?