Re: Potential owner of a 535i
When I collected my 135i, I used Vpower. Then 98. Then 95. haha. Didn't make much diff except on my wallet. But I sticked to 98. Psychologically it makes me feel better and faster. Look up the manual. It says 95 is sufficient. These BMWs have modern TC engines. Not some old wrx or evo TC engines which require higher octane hence 98 up is better.
But just remember to cool down the car abit (30sec or so depending on when you WOT, boost) before you switch off the engine. Afterall it is a TC car. Unless you have a turbo-timer installed.