I'm local to the Lower Mainland of BC, home to the worst gas in Canada. For reference, I'm running a MK7 R with EQT Stage 1, 91.
Prior to the borders closing, all I ran was 92 Washington blend, which is e10.. my logs were quite clean and the car ran solid.
When that was removed as an option, I filled with Shell 91 and ran a log... all I can say is YIKES.. I was seeing -4 / -5 corrections, across all cylinders, at full throttle. The EQT maps are way, WAY too hot for our sh!t gas in BC and it's not even close. I previously logged Shell 91 and Chev 94 on a JB4 and found them about the same, both being inferior to 92 E10 from Washington but still looking reasonably safe (21 psi on the JB4 vs 28 psi on EQT).
I asked EQT about a low-torque version of their OTS map.. they are not interested in providing the option and suggested a pro-tune. I considered it, but TBH $500 USD for a dumbed down, lower power map on a mechanically stock car didn't seem that compelling to me. If I was going with a pro-tune, I would probably want to upgrade the DP and IC.. but I just want to keep it simple with this car right now and feel the 'bang for the buck' falls off very quickly after the massive stage 1 returns.
The issue we have here, is that all of our supreme gas is ZERO ethanol (caveat below). We absolutely cannot compare our gas to any locale where ethanol is blended into the supreme.. it's just apples and oranges.. or apples and monkey pi$$.
One interesting point relates to Chevron.. I have spoken to a few Chevron attendants and I understand that they only have two in-ground tanks, even though they have 87, 89, 91 and 94 octane pumps. I was told that the two tanks hold 87 and 94.. 87 will contain ethanol. The 94, as is the case with all supreme gas locally , has zero ethanol. I am defining supreme gas as being the highest octane offered at a given station.. Chev 91 is therefore not supreme, even though 91 Shell is (since Shell has nothing higher).
I was told that the 89 and 91 Chevron pumps are actually blending 87 and 94 gas from the in-ground tanks.. therefore, the 91 Chevron gas should theoretically contain some ethanol and therefore it should be superior to any non-ethanol version of 91 (Shell, Petro Can etc).
I haven't logged Chev 91, but it would be interesting to see the results.. Regardless of whether it's better than other 91 offerings in BC, I know it won't be as good as what I am doing personally: Blending ethanol into the pump gas myself, like a complete OCD nutjob (having to organize the logistics of jerry cans, e85, planning fill-ups etc. seems pretty damn whacky for a daily driven Golf R). If I was filling up once a week, I don't know if it would be worth it to me, but I really haven't been driving a whole lot this past year.
The good news is that when blending either Shell 91 or Chev 94 up to about E13-E15, the logs are PERFECT. I mean, zero corrections, anywhere in the rev range under full throttle.
For those of you in BC without the option of buying some ethanol and blending.. I would say you're looking at a pro-tune, or staying stock. I would be very cautious of running any OTS maps, with our horrible pump gas.
Cheers
This all being said, depening on the price and for the winter, I'll likely end up just filling up with Costco 91, as they are also a Top Tier brand.
