daking1959

A local EZ Stop has 87 octane gas without ethanol, is the octane level high sufficient enough to use in these engines?
Ive been putting 93 octane in the car since Ive had it (2012)
dk

ygmn

What does sticker in gas cap say your car needs as Minimum Octane?
as that is what you need or higher - try not to go lower unless it means walking.

Low octane reduces power since engine will retard timing due to engine knocking from predetonation.
ONly just exceed minimum unless you have it tuned for another octane rating.

mcgsxrclk500

I'd bet these motors were designed with 91 octane (hi test) in mind.

When I had my 1969 Thunderbird, I always used Shell premium, as it was 91 octane and no ethanol. For a car that old, ethanol was never around in its time, so if you use gas with ethanol in it, you risk issues with gas line damage, and carb seal damage.

I doubt ethanol matters for a car built in the 2000's.

For my CLK, I use the same Shell 91, but would use Sunoco 94 (does contain ethanol) if I could not find the Shell station.