View Single Post
      12-29-2012, 11:25 PM   #58
nospam
Captain
17
Rep
675
Posts

Drives: 2015 Alpina B6; 430i; X5 40e
Join Date: Jul 2010
Location: Orange County, CA

iTrader: (0)

I'm fairly certain that BMWs since the N54 are adaptive and will advance timing on higher octanes (93+) and environmental factors). I know there will be performance gains, not sure about gas mileage impact.

I just read that ethanol is often used to increase octane so that 91/92/93 gas may have more ethanol than 89 and perhaps lower mileage will result.
Appreciate 0