chadchm8

I have 2 Hpi rush evo stadium trucks that i recently installed 2 18ss engines in. For the first two weeks (after properly breaking it in) the two trucks ripped through my racetrack. Me and my brother went through about a gallon of gas over the first month. I tune the motors each time i use them to match the condtions (can you tell i care for them?). Now, i am noticing no matter how i tune them, they both get really hot compared to what they used to. They constantly stall out and i cant figure out why. I asked my local hobby shop and they said my motor was tuned right (not too lean to cause heat, not extremely rich to cause lots of heat) Could my problem be my stock exhaust or fuel lines or 20 % fuel. I use the 18ss carb, and my filters are clean, and the inside of my motor is also (i checked). Somebody help please, i dont want to have spent $350 for nothing. The only thing that i can think of is the exhaust. People say that exhaust stinks anyway. I also use the stock air filter which may be a bit restrictive