hairbear21

I wanted to post this because a while back there was discussion about lower octane fuels and using ethanol blended fuels. This is DIRECTLY form the owners manual of my 95 Z28

Fuel
5.7L LT1 (Code P)
The 8th digit of your vehicle identification number
(VIN) shows the code letter for your engine. You will
find the VIN at the top left of your instrument panel.
(See “Vehicle Identification Number” in the Index.)
Use premium unleaded gasoline rated at 91 octane or
higher. You may use middle grade or regular unleaded
gasolines, but your vehicle may not accelerate as well.
The gasoline you use should meet specifications ASTM
D4814 in the United States and CGSB 3.5-92 in
Canada. Be sure the posted octane for premium is at least 91 (at
least 89 for middle grade and 87 for regular). If the
octane is less than 87, you may get a heavy knocking
noise when you drive. If it’s bad enough, it can damage
your engine.
If you’re using fuel rated at 9 1 octane or higher and you
still hear heavy knocking, your engine needs service.
But don’t worry if you hear a little pinging noise when
you’re accelerating or driving up a hill. That’s normal
and you don’t have to buy a higher octane fuel to get rid
of pinging. It’s the heavy, constant knock that means
you have a problem.
What about gasoline with blending materials that
contain oxygen (oxygenates), such as MTBE or alcohol?
MTBE is “methyl tertiary-butyl ether.’’ Fuel that is no
more than 15% MTBE is fine for your vehicle.
Ethanol is ethyl or grain alcohol. Properly-blended fuel
that is no more than 10% ethanol is fine for your
vehicle.
Methanol is methyl or wood alcohol.
NOTICE:
Fuel that is more than 5% methanol is bad for
your vehicle. Don’t use it. It can corrode metal
parts in your fuel system and also damage plastic
and rubber parts. That damage wouldn’t be
covered under your warranty. And even at 5% or
less, there must be “cosolvents” and corrosion
preventers in this fuel to help avoid these
problems.