I bought a new (0 miles) 09 Z1 Turbo last month and am in the process of making sure I have my ducks in a row. I know I need to run 91 octane or better and also know that's not always available. What does anyone recommend for an octane booster to carry with me just in case? This leads to the next question, is 10% ethanol ok as long as the octane is where I need it to be? Unfortunately the ethanol is all too common around here. Thank you for your time.