Directly from the horse's mouth:

See item 13, in particular:
http://www.chevron.com/products/prod...rgas/8_q-a/#22

Only very high performance cars benefit from "premium", otherwise it is a
waste of money. Certainly a waste of money for anything that uses gasoline
around the house.

You may also find the item of interest that refers to how long you can keep
gasoline.

--
Walter
www.rationality.net
-
"George" wrote in message
...
I just bought a Stihl string trimmer, at a dealer. I'd read on the net
that Stihl engines require at least 89-octane, but hadn't seen anything
about that in the literature. So, I asked.

The sales guy said that they didn't _need_ high octane, but you should
_use_ "premium" gas ("93"), because it's "cleaner", that it's filtered
more, and that "cheaper" gas would gum up the carb.

I was a little surprised at this, but there's a lot I don't know. I
don't see where he had any reason to lie - I was already buying the
thing.

Does anyone know whether there's any truth to this?

Thanks,
George