That's funny because Shell is worst for our engines because of their factory additives. Always felt sluggish when pumping shell. Stopped years ago.



Ofcourse all gas comes from the same reservoirs in the ground. Then they get sorted to the refineries. Just because gas usually comes from the same reservoir, it doesn't mean 100% of it is great. CA basically gets the brim of the barrel, our 91 sucks compared to other states with 91. Simple put, theres different levels of "pureness", CA gets some of the crappiest tier.

Ditto.

-Brian

hmm ya figured it was additives/ how they refine the fuels.

so PhoShizzle, youre saying that because Shell is trying so hard to keep their consumers' engines clean and healthy, that they are actually damaging them?? now thats a meme ill be waiting for. lol

You're telling me this is the first you've heard of this.......?



While Petrol brands are good for some engines, they might not hold true to performance for other types of working engines.

fair enough. now that i see you're speaking of just Subaru/HP engines. and ya, i deff agree. Our engines are prob the pickiest I have ever seen. even just the coolant, I have always forked out the extra $$ for that better piece of mind that my aluminum crankcase is being well taken care of. I was speaking more on the broader basis. Everyone, all cars worldwide. The way Shell advertises how well their gas is supposed keep your engine clean , t hen you stated how they were among the worst for engines. But ya i agree for our cars and other high performance cars out there a lot of the additives are crap. but i also dont deny that for the avergae consumer (i.e my 2012 camry....dont hurt me! lol), it does in fact take care of some of the un needed crap inside the engines.

I self tune, and I was pushing limits (AFR higher than I'd run anyone else's car, but I log religiously and had gauges, so I could tell if there was a problem.) It was noticeable, and not just a one time thing. I stopped using Chevron, and a couple years later was in LA visiting a friend and filled at a Chevron since it was there and I didn't know the area well... IMMEDIATE knocking if I leaned into it.

Like I said, I've been on E85 for a few years since we got a 3rd vehicle and mine never leaves the immediate vicinity. So this is pretty old info, but I had better luck with other brands in my car.

Who really cares about additives anyway. run some fuel system cleaner or Seafoam every once in a while. What really matters is knock resistance.