Twice a year my family and my self, travel from Monterrey to Mexico City, that means 1800 KM (1118 miles) round trip. Since new the fuel consumption for one way was 2.75 tanks (each tank is 45 liters or 12 us gallons). For this holidays (Xmas '06) I used 5.25 oz in the first two refill tanks (in total 2 bottles). Of course increase horse power, I feel better the engine, but the amazing: I spend only 2 fuel tanks from Monterrey to Mexico City trip (900 km - 560 miles). Thank you LUCASOIL.