As spring slowly approaches, I hope to have the car out of storage in 2 or 3 weeks, and am worrying about this ethanol issue. Will we need to add anything each time we fill up, or still just stick with the premium fuel and hope it doesn’t cause any issues? I imagine there are many high end cars that would be impacted by this, so I assume we will be ok. Thoughts?
Dale
I know that this is a somewhat controversial subject on this forum and, until now, I have abstained from expressing an opinion. However, your question demonstrates just how much misinformation has been spread about the "evils" of ethanol blended fuels and their supposed detrimental effects on an ICE and its fuel system. That may well have been the case for engines that were manufactured 20, or more, years ago where the fuel systems were not comprised of stainless, ceramic and synthetic materials that, in our C7's, are impervious to the effects of ethanol deterioration. In the case of the C7, and virtually every modern day ICE vehicle, it was designed, engineered and built to safely utilize fuels containing up to 15% ethanol. This is not just my opinion but also that of the manufacturer.
From the 2019 GS owner's manual:
"Recommended Fuel (LT1 6.2L V8 Engine).
Do not use any fuel labeled E85 or FlexFuel. Do not use gasoline with ethanol levels greater than 15% by volume. Premium unleaded gasoline meeting ASTM specification D4814 with a posted octane rating of 93 is highly recommended for best performance and fuel economy."
To take this a step further, I had the opportunity to be part of a discussion on this very subject at the 2018 Corvettes at Carlisle event. At the center of the discussion was one of the engineers from the original LT1 engine design team at Bowling Green. He stated that there would be no detrimental effects on the C7 as a result of using the recommended fuels listed in the owner's manual, including ethanol blended fuels. The indication that ethanol blended fuels, of 15% or less, are harmful to the C7's fuel system and engine was summarily dismissed. He further emphasized the fact that the vehicle was designed to run on said fuels and that there were, in fact, some inherent advantages in terms of moisture absorbency, increased combustion efficiency and, as a result, a slight decrease in HC and CO emissions. These are facts that I was already aware of but it was good to hear someone in "authority" dispel some of the misinformation surrounding this subject.
Dale, in short, don't worry about using 91 to 93 octane, Top Tier, ethanol blended fuel of 15% or less. It will not harm your vehicle. Just my opinion, and that of a GM engineer. I know that there are others who will disagree, just the joys of living in a free country.
Best regards
Ross