it’s because our midgrade has constantly been 89 and premium was 91 in many parts of the country.
90aki is enough for 99% of the engines on the market. if you have time on your hands you can mix it up yourself
Using higher than recommended octane fuel can result in incomplete combustion?
- Thread starter The Critic
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90aki is enough for 99% of the engines on the market. if you have time on your hands you can mix it up yourself
This is an interesting area to consider. Having watched the live data from my pickup (a Honda) rather a lot, it’s amazing how small an incline causes the % load to reach over 90% just to maintain speed. Simply going along the freeway up and down over overpasses causes it.
Because fuel efficiency is generally better at low rpm and high throttle openings, and because even semi-modern vehicles are programmed to hold gears as long as possible, that’s a situation where it seems higher-AKI fuel (in an engine capable of adjusting to use it) _could_ give meaningful advantage.
What am I missing?
To be clear: whether said advantage is adequate to compensate for the higher price of high-octane fuel is a different question.
Is the % load in the live data based on the throttle opening? Is this on cruise control?
The %load in the data is not simply a throttle position sensor reading, if that’s what you’re wondering about. I think I recall that it’s a calculated load (so throttle position may be part of the calc) expressed as a percentage of what the engine ‘could’ make at whatever rpm it’s turning.
It will kick down a gear at just a bit over that %load, and I’ve watched it both on cruise control and when driving without.
I hope that answers what you’re asking about(?).
It will kick down a gear at just a bit over that %load, and I’ve watched it both on cruise control and when driving without.
I hope that answers what you’re asking about(?).
Remember that load % can go well over 100%, especially on turbo cars. You should really establish what the max is for your engine before the number gets any meaning.
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My 2013 Tacoma V6 knocks/pings using 87,89, and even 93. Less so with 93. I just use 87 and deal with it. I took it to a Toyota dealer to get the TSB done that flashes the ECM to try and correct it. It helped but it’s still there but not as bad. I used 93 daily because I hated hearing it, I’m sure the engine doesn’t care for it either.
Somewhat under 100% (high-middle 90s) is the most I’ve ever been able to get this vehicle’s data stream to show, even when making a direct effort to see what I can get it to do.
I’m not sure the absolute number argument is relevant to the point, though. If high-AKI fuel allowed this engine or vehicle to achieve 110% load, that would be exactly the power increase I pointed out as interesting to explore as a potential practical benefit to higher-AKI fuel in engines that can take advantage of it.
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No, turbo cars can get to 170% and more. I suppose it reflects the boost level. 90% doesn't mean much if you can go up to 170 or more...
Colorado has been acting the same way lately, lugging and falling on it's face with the slightest incline on 87. 89 has made it better but I am really interested to see in Non-ethanol 90 will make it even more so. I got a couple of knock codes on the highway a year back that gave me pause and then I started listening and you can hear it ever so slightly.
