I have some quetions regarding nitro fuel. How long will a gallon of gas last? How many tanks of gas (150cc) will a gallon of nitro fuel fill? It says using 33% traxxas top fuel will not wear out you engine faster than using 20% or 10%. Is this true? And on that topic how much differnt will the tunning range be when using 33% compared to 20% and 10%'s tunning range? This may also be kind of off topic, but what's the best and most easy way to tell if you engine is running lean or rich WITHOUT risking damaging something?