deposits
least higher
performance. Subaru's
is up to $2.25 for premium. Is mixing 50% 83 with
car that does not require premium is OK but premium gives nothing
except cost.
Well, I have a 1998 Forester that just turned
216,000 miles on the odometer, and I am still running 87 octane, as recommended in the manual. I guess it takes longer than that for the "notorious carbon buildup".I would use whatever grade is specified in the manual. Saving a few pennies on gas at the expense of the engine is false economy. Conversely, using a higher octane than required is throwing money away.