RE: Club FOX!
I have experience with only 1 Fox engine, an Eagle 74. I bought it used, but shoulda bought it new and saved myself a lot of trouble. You can learn a lot from reading this whole forum, but at least read some.
The new Fox engines have the new head buttons and carburators, making them very easy to tune. However, it is still a low nitro engine and requires a long break-in period. I use 0-5% nitro. Others here claimed 10% works for their latest version. What I would do if I were you, is run at least a gallon of fuel through it on the bench. Get you some earplugs and a good book and relax while breaking it in.[8D] I think most, including Fox Manufacturing, recommend some castor oil in the fuel.
I'm looking forward to next flying season, I had been using an MVVS muffler on it. Next I will try a homemade mousse can muffler. Finally, I will promote it to a Jett muffler.