Octane - 94 w/ up to 10% ethanol - any issues?

[Phil_R]

I did some searching and found a similar topic regarding 93 octane w/ 10% ethanol. This question is more about harm - i see the owners manual makes some mention of avoiding higher than 15% ethanol blends. In Canada, we have Petro-can that runs 94 octane but with up to 10% ethanol. I've been running it in my GTO for 5+ years now w/ a handful of mods and dyno-tune and i've never seen any kind of issue, but that vehicle only sees seasonal use.

I've witnessed first hand a friends Saab Turbo (mind you, a 10 yr old car) which would ping/pre-det like crazy on 94 octane w/ ethanol, but then have no issues on 91 octane Shell fuel with 0% ethanol.

Being that I will be daily driving this car, and it is currently stock - should I be running the 91 octane with no ethanol? or the 94 with up to 10% ethanol? Or am I overthinking this - and it probably doesnt matter as far as longevity is concerned (i have a feeling this is the reality)...

I also thought that i could feel an increase in power when i put in the 94 octane w/ 10% ethanol over the 91 - but this is a new car to me and still getting used to it - it may have been in my head.

Thanks,

 

[CanadianGuy]

The ECU on this vehicle is quite forgiving. Been using the 94 since the begining but its only been 1600 km.

 

[me32]

Youll be fine. All new cars are made to run 10-15% ethonal

 

[COBB Tuning1]

My experience with Canadian 94 octane fuel has not been good and it usually performs worse than 91 octane. I would recommend a local 91 octane fuel from a Top Tier brand, preferably with E10.

Ian

 

[Phil_R]

Problem is, we seem to have Shell 91 w/ no ethanol, or every-other brand out there with 91 w/ up to 10%. Petro-can is the only one that offers above 91, and it has up to 10% ethanol also. So with your comment, it seems there are no real winners here.

Does the "E10" have any discernible effect on longevity or reliability?