I wouldn't worry about rushing out and getting the motor modded. It will run great out of the box. The main beifit of modding this engine is to improve runtime. You'd pay more for the mod than the engine actually costs. I mod many of my own engines which keeps the cost down for me. If you treat it good(keep the dirt out of it and keep the temps around 230)most of them will last for 6-10 gallons without any problems. Once in a while you run into a lemon but, most hold up very good.
Again, Just run it as is until you get a dozen or so races under your belt. You'll learn a lot in that time. Your better off spending the extra cash on racing tires. Hint, Hint......