The manual calls for 60 ounce servos on ailerons, rudder, and elevator. The 4721's are overkill, but it beats buying servos when you don't need to.

The firewall is around 4 5/8" wide and the cowl is the same width.

If your muffler is 5 1/8 wide, you got 1/2" sticking out the side of the cowl, and if its the same as mine, it won't be just one side. It will be centered up so that there is about a 1/4" sticking out each side.

I am thinking about getting a small header to put on the engine and some flex pipe to run out the bottom of the cowl.

I don't know how this will affect the engine performance though and I imagine it might not get past the field noise police.

If anyone knows of a muffler that will work without butchering the cowl, please let me know.

Todd