This was "System 3" gasoline according to their promotion.
I was on the testing committee with their chemists.
>"if your car doesn't call for premium gas, there's no point in getting premium gas".
You are correct to a certain extent, but this is one of those cases where you really need to see for yourself since your actual mileage may actually vary a lot more than you think.
87 octane is figuratively speaking kind of the "bottom of the barrel".
You may find with many cars anyway "if you don't want premium performance, there's no point in getting premium gas".
My GTI has a 2L 4 cylinder engine. In was EPA mileage rated on 87 octane gas, and the fuel door has a stamping to inform the user it wants 87 octane. HOWEVER, VAGs official claim is that the engine makes it's rated power while using 91 octane. Previous versions of this engine were EPA rated with 91 octane.
My pet conspiracy theory is that VAG were "cheating" on more than just diesel emissions, and that on 91 it leans the fueling way out for more efficient power and economy ratings a full 20% higher than claimed, but on 87 the system pulls way back and just dumps fuel into the chamber to control knocking and keep NOx emissions down, which results in the absurdly low claimed fuel economy.
>My pet conspiracy theory is that VAG were "cheating" on more than just diesel emissions, and that on 91 it leans the fueling way out for more efficient power and economy ratings a full 20% higher than claimed, but on 87 the system pulls way back and just dumps fuel into the chamber to control knocking and keep NOx emissions down, which results in the absurdly low claimed fuel economy.
Why would they do that? It sounds like from what you're saying that the engine was designed to run off 91 octane gas (it was more efficient and provided more power), but for whatever reason they felt obligated to market/test using 87 octane gas? Is it purely economics (ie. premium costs 26% more than conventional[1], but you only gain 20% more fuel economy)? Is there some government regulation that penalizes cars that "officially" use premium gas?
To clarify, my conspiracy is that on 91 octane that the engine is designed for it is able to run leaner and hotter in the combustion chamber, which makes more NOx emissions than are allowed, so they just added a map to the ECU that limp modes the engine a bit on 87 so there's reliably no knocking and lower emissions, and they don't care that mileage takes a hit because nobody who buys a GTI will put 87 in it, because we are "enthusiasts". IE I'm saying I think the car can't pass emissions regulation on 91.
It's 110% a conspiracy theory. I could test it by going to a shop that does emissions testing once on 87, and once on 91, or by carefully logging certain parameters through ODB2 on both types of gas. I just.... haven't
Something to think about, now that so many decades have passed since the octane test methods were fully standardized in the USA;
Auto and oil companies have had the same number of decades to come up with more "interesting" ways to game any numbers involved.
The EPA didn't even get concerned with gasoline until relatively few decades ago, and their input has been more from the standpoint of a "pure" bureaucracy.
It was a little company called Texaco.
This was "System 3" gasoline according to their promotion.
I was on the testing committee with their chemists.
>"if your car doesn't call for premium gas, there's no point in getting premium gas".
You are correct to a certain extent, but this is one of those cases where you really need to see for yourself since your actual mileage may actually vary a lot more than you think.
87 octane is figuratively speaking kind of the "bottom of the barrel".
You may find with many cars anyway "if you don't want premium performance, there's no point in getting premium gas".
Trucks too.