abqhudson

Is there a difference in performance when running premium gas?? Is there a real world difference between PZEV and e85 engine in 2014 C300? Any help would be greatly appreciated.

Adi-Benz

Most people feel a reduction in performance when they use e85 vs. premium.

Your gas mileage is also worse.

// Idk about "different engines" though.

michail71

While having less efficiency I thought ethanol had a higher octane rating and allowed for better timing and performance? I think it becomes a matter of the fuel pump being able to flow at higher rates.

I'm not too up on ethanol but it might not matter too much as Mercedes tunes for 91 octane.

Adi-Benz

There are several threads out there. I won't link you, because it's a simple google search.