[NaughtyGT]

I do believe (all due respect) it's about time for the "research" advice button to be pressed? There is a miriad of information regarding the best/most practical/scientific way to gain power/keep economy. My two bobs worth: High octane (95-98) will keep engine clean, aid response & hinder the need for tuning & injector cleaners. The trick is to get the car clean & running well, then keeping it that way. The higher the octane (no matter the comp ratio) the cleaner, better performance & less maintenance you will experience!