Re: 89 octane OK in 2.8L V6?

["Craig D. Niederst" <niederst@telerama.com>]

Mark,
My impression of the 91 octane requirement for this engine is for both the
performance aspect and also the fact that it burns cleaner. Higher octane
fuels are slightly more volatile than the regular grade fuels, so they burn
cleaner. This reduces the sludge and soot that are part of the combustion
process, and keeps the valves and fuel injectors cleaner. I now always run a
minimum of 93 octane in my '92 100S, and even use 94 octane when I get a
chance (local Sunoco has it for less than 93 octane on Wednesdays). I've
tried 89 octane before, and I can tell the difference in both performance
and mileage. I'm guessing that the longer mileage achieved in using 93
octane probably makes up for the price difference, and gives the benefit of
cleaner injectors and valves. Just my $.02.

Craig
'92 100S (72k)