Octane experiments

For the last few months I have been running 91 octane E0 when it's available. It makes the hybrid perkier and faster, and 8-10% better MPG. The biggie is how it smooths it runs, very noticeable all the time and most obvious when the ICE first fires up.
 
I've always just put regular gas in my vehicles, never saw the need,

My guess is the higher octane is holding timing and it's just enough to pull the grade. This to me is more than anecdotal, in 4 years of traveling this road in every condition the Xterra has always downshifted, now with both 89 & 91 it has not downshifted one time. Is this little thing enough to make me want to run 89 at 25 cents more per gallon? Likely not. On our next towing trip I'm going to run some tanks of 89 out of curiousity.

Ever try 88e15?
It’s 20 cents cheaper than RUG.

In my experience I get more power from it than 89

If auto manufacturers get a legal minimum 88e15 will be the legal minimum
 
I get premium at the local Costco, they usually charge $0.12CAD per litre more versus 87 compared to $0.34 per litre at other stations. I rationalize the use of Costco premium because I have seen a slight increase in power and milage (kilometreage?) when I use it in the QX60. The fuel door sticker says that best performance comes with 91 octane. Not going to do any scientific testing, but I can afford it for the 18k kilometres of annual driving I usually do. If I didn't have a Costco gas bar near me, well I doubt I'd bother spending such a large amount over 87.
 
For the last few months I have been running 91 octane E0 when it's available. It makes the hybrid perkier and faster, and 8-10% better MPG. The biggie is how it smooths it runs, very noticeable all the time and most obvious when the ICE first fires up.
Impossible... need to plug a scan tool in as all opinions and experiences mean nothing on this forum(unless a sponsor product is involved).
And, mpg data is meaningless without tracking for several bazillion miles, and then some. Smoother.... did you measure that with a smoothometer? Without the data from the smoothness meter, it must be all a placebo. Perkier? Which make/model perkmeter are you using? Faster? no way... you actually looked unsafely away from the road and looked at the speeding-o-meter? :ROFLMAO: 😉
 
Impossible... need to plug a scan tool in as all opinions and experiences mean nothing on this forum(unless a sponsor product is involved).
And, mpg data is meaningless without tracking for several bazillion miles, and then some. Smoother.... did you measure that with a smoothometer? Without the data from the smoothness meter, it must be all a placebo. Perkier? Which make/model perkmeter are you using? Faster? no way... you actually looked unsafely away from the road and looked at the speeding-o-meter? :ROFLMAO: 😉
Sponsor product? Sounds like sour grapes to me rather than sound technical reasoning.

You’re getting more obtuse as this thread devolves.
 
I remember reading a post on a mower forum where a guy said he always runs Premium in his ZTR with a two cylinder Kohler engine . He claimed that his mower would " Start quicker , make more power , and run cooler " ... These kinds of threads remind me of that nonsense .
Is there nonsense in this thread? I tried mid and premium and only noticed not downshifting on 1 specific grade. No reason to spend more for gas. Thought maybe I'd get some of Hermann's experience but didn't happen. I'd like a perky Xterra.
 
Obtuse are those with feelings
And yes, there will be those that add nonsense

Enjoy my sarcasm. Sorry if some can't feel anything with a CEL.
 
I remember a world with people that did things themselves and had even 'senses' available that they'd notice something. Now, most just rely on headmeds and go thru life glued to their phones like zombies and drones, and wouldn't notice a barn wall until they crashed into it, and then only maybe notice the hole in the barn behind them.

Sorry world we live in. The days of using senses are gone. I can hear and identify engines starting or running across a large parking lot, and hear issues with many of those engines from a distance. I can feel the difference among identical engines simply by putting my hands on them. But most fools wouldn't even notice a spark plug missing without a scan tool. I guess those of us that worked with carbs/distributors are a dying bunch, as is anyone that got their hands dirty in an industrial setting.

Stick with your tuning shops, dealers, forum hype, and indie mechanics. Most are too useless to even make comments.

I might be misunderstanding your posts, but you seem to be resorting to name-calling to discredit other members who don‘t agree with ”butt-dyno“ test results.

You also seem to be be overly-generalizing. Many of us can tell a great deal about what the car is telling us just by driving. That shouldn’t negate the fact that if there isn’t actual sensor data to back up a butt-dyno anecdote, then that data shouldn’t be weighted as heavily (and considered nearly as accurate) as other data points, such as from data-loggers.
 
Obtuse are those with feelings
And yes, there will be those that add nonsense

Enjoy my sarcasm. Sorry if some can't feel anything with a CEL.
I had a scanner with 88e15 and 89

Knock count and timing was slightly better on e15 than 89

Antidotal as every car is different but not an mpg measurement
 
I remember a world with people that did things themselves and had even 'senses' available that they'd notice something. Now, most just rely on headmeds and go thru life glued to their phones like zombies and drones, and wouldn't notice a barn wall until they crashed into it, and then only maybe notice the hole in the barn behind them.

Sorry world we live in. The days of using senses are gone. I can hear and identify engines starting or running across a large parking lot, and hear issues with many of those engines from a distance. I can feel the difference among identical engines simply by putting my hands on them. But most fools wouldn't even notice a spark plug missing without a scan tool. I guess those of us that worked with carbs/distributors are a dying bunch, as is anyone that got their hands dirty in an industrial setting.

Stick with your tuning shops, dealers, forum hype, and indie mechanics. Most are too useless to even make comments.
I have the forunate history and age of both the old-school muscle cars with a screw driver tuning a carburator and the new school turbo 4s with ECUs and scan tools. Glad I can do either but your average person chiming in online that they filled up a modern vehicle calibrated to be able to run 87 with 93 and feel this and that is as my meme above suggests. Enjoy telling the neighborhood kids to get off your lawn.
 
I had a scanner with 88e15 and 89

Knock count and timing was slightly better on e15 than 89

Antidotal as every car is different but not an mpg measurement
That is exactly what would be expected.
 
I get premium at the local Costco, they usually charge $0.12CAD per litre more versus 87 compared to $0.34 per litre at other stations. I rationalize the use of Costco premium because I have seen a slight increase in power and milage (kilometreage?) when I use it in the QX60. The fuel door sticker says that best performance comes with 91 octane. Not going to do any scientific testing, but I can afford it for the 18k kilometres of annual driving I usually do. If I didn't have a Costco gas bar near me, well I doubt I'd bother spending such a large amount over 87.
And for your vehicle, yes...it's tuned to take advantage of it and yeah, Costco is the cheapest 93 in my area...only about $0.30 more per gallon so I use it for my three vehicles that require it.
 
Is there nonsense in this thread? I tried mid and premium and only noticed not downshifting on 1 specific grade. No reason to spend more for gas. Thought maybe I'd get some of Hermann's experience but didn't happen. I'd like a perky Xterra.
What experiences are you wanting to know about. My last tank in totally below 32° with mostly temps in the upper teens to low 20's at high speeds with strong direct sidewinds of 30+ mph., is going to suck. Probably around 35 MPG if my grade school math is still correct in my head. It is the E0 and ambient temps that makes the difference. Wish I could buy lower octane E0 for less money but I really enjoy the smoothness of the engine now. Just took a 25 mile trip. Difference today is it is 55° and the mpg's were above 40.
 
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And for your vehicle, yes...it's tuned to take advantage of it and yeah, Costco is the cheapest 93 in my area...only about $0.30 more per gallon so I use it for my three vehicles that require it.
Is it ethanol free.
 
Is it ethanol free.
No...E10. E-free fuel is pretty hard to find and no real reason to run it I can see, the mpg difference between it and E10 is so slight I can't believe folks can even measure it reliably. I run E20 blended in my Sportwagen and I can see only a slight drop in highway mpgs if I keep variables constant.
 
Obtuse are those with feelings
And yes, there will be those that add nonsense

Enjoy my sarcasm. Sorry if some can't feel anything with a CEL.
Your tuning company would be great.
You: "Custom tunes, adds 100hp, no logging needed!"
Potential customer: "Can you show me your dyno sheet or some logs?"
You: "No, I just need to Jedi-touch it or hear it and I'll be able to adjust the fuel/timing/boost. If you can't tell how much power was added or what adjustments it needs I guess you really shouldn't be in this game."
Customer: "Ok cool, I'll take it!"
Car blows up.
 
What experiences are you wanting to know about.

It makes the hybrid perkier and faster, and 8-10% better MPG. The biggie is how it smooths it runs,
^This. All I got running 91 was one less downshift on one hill. 8-10% better mileage is impressive if you're hand calculating it over multiple fill ups to verify.
 
^This. All I got running 91 was one less downshift on one hill. 8-10% better mileage is impressive if you're hand calculating it over multiple fill ups to verify.
I do hand calculate, 90% of the time, at the same pump. Now 8 tanks into this routine. Although with the crazy temp swings it will be April-May till we have consistent temps around here. When the weather is consistent It is easy to compare. In late fall the consistent weather would show 3-4 more MPG in for E0.
 
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GM and a few other makers have stated they want a new high octane standard. They can build engines that get higher fuel economy along with lower emissions. The problem is that most are addicted to the cheapest gas at the pump. GM doesn't want Joe Dumb buying a new GMC Sierra that needs high octane and filling it with 87. We are not getting the more fuel efficient gas engines we could. They are working with the petro industry on ways Joe Dumb doesn't put 87 octane in his truck, but the auto makers really just want 87 to go away like leaded gas did.
And before my time, some people bought 1975 cars that had a catalytic convertor and used a funnel so they could buy the cheaper leaded gas.
It's rumored that 87 octane fuel burns hotter and therefore keeps the valves cleaner on a multi-port injected engine that has low enough compression to safely run it; however, I'm not sure if it would make a difference on direct fuel injection.
 
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