The Webra Q500 engine you bought will be a great engine for sport flying. The only distraction will be the carb. It doesn't draw fuel very well and needs a lot of fuel pressure fed to ithe carb to work well throughout its range. I would suggest adding a one way check valve in the muffler pressure line to the fuel tank. This will lock in a larger amount of pressure than you will normally see from straight muffler pressure. The second option would be to pick up a "TN" carb from webra. this is a more typical barrel style carb that works great for sport applications.

Good Luck!

Pete