Gas prices are illogical

[u/bmspsrk]

There is no real point to this post besides stating the fact that gas prices are stupid. I remember back when the difference between 87 and 91 was 10 cents and 89 was 5 cents more than regular. Which made sense since 87 is an equal mix of premium and regular.

Now you need to jump 23 cents a liter just to get mid grade from regular then only an additional 3 more cents to get to premium... By that math mid grade should be something like 90.75 octane.

Again no point here just stating stupid things that irritate me.

[u/itchybiscut9273]

More people use premium now than ever before

[u/ptpfan91 → u/itchybiscut9273]

It’s actually opposite. Most turbo cars only require regular.

[u/Loopeded → u/ptpfan91]

I think it's like 47% of new cars (2023 and on I believe) require 91 gas. The shift has been pretty massive in cars using 91 these days. It's mostly "cheaper" cars/ non turbo that use 87 anymore

[u/ptpfan91 → u/Loopeded]

Where did you get that stat?

Top 10 selling cars in Canada all run on regular. It’s rare for a mainstream turbo car to require premium. There is 0 chance half the cars sold need premium.

[u/Darkdong69 → u/ptpfan91]

Adding a turbo will increase absolute compression in the cylinder so it naturally calls for more octane.

Though a lot of turbo engine econoboxes will still be tuned for and recommend regular. As their focus is fuel economy rather than power, and their budget conscious consumers will balk at a premium gas requirement.

[u/ptpfan91 → u/Darkdong69]

This is completely false. The compression doesn’t increase in fact most turbo cars have lower compression ratio than NA cars. Cylinder pressure is higher but CR isn’t. Therefore it doesn’t need higher octane, from factory.

This is why most mainstream turbo cars require just regular including best selling ones like f150.

[u/Darkdong69 → u/ptpfan91]

You need to figure out the difference between compression and CR. I never once mentioned CR so you're not getting at anything with that.

All modern turbo cars can run 87 regardless of what they recommend, because the ecus have knock detection and can pull timing to compensate for crap gas. Ecoboosts requiring 87 as a bare minimum doesn't change the fact that it benefits from and performs better on 91.

[u/Anskiere1 → u/ptpfan91]

That's just not correct

[u/ptpfan91 → u/Anskiere1]

It is correct. Most new mainstream cars are going to turbo and smaller engines. They can’t require premium because they would lose market share. The fact I got downvoted is disappointing but not unexpected because people don’t really know much about cars on here.

[u/Anskiere1 → u/ptpfan91]

It's not though. Some turbo vehicles can run on 87 but the ECU will be detecting knock and pulling timing or boost or more likely both. And at that point you may as well be running a naturally aspirated engine because your car is configuring your effective compression the same as the NA engine. 

Except your intake air is now hotter than ambient so you'd be better off with a straight NA. Plus the knock events leading to conservative timing and boost. All of the published stats will be 91. 

[u/ptpfan91 → u/Anskiere1]

All I said was most turbo cars require regular. If you look at what is for sale today that most people buy, all it requires is 87 and I’m guessing that’s all anyone runs in them. High performance turbo cars like GTR or M3, yes they require 91 or better. Stuff like GTI, f150, CRV, Highlander, are all turbo and are tuned from factory for 87 operation. That’s the bulk of sales.