Does 89 octane save, and is 93 octane even better?

whippersnapper02 said:
I'm running 91 again due to pinging. MPGs are still at 15.5 to 16 all street.
Click to expand...

I'm not questioning your word, or being sarcastic. Not at all. This fascinates me. But ... I don't see how that's possible.

If your engine was pinging, then it couldn't possibly have been running at optimal power. That means lower mpg, ceteris parabis.

Second, if it was pinging, then the computer retarded timing causing further loss of power. That means further lower mpg, ceteris parabis.

Third, even after the computer retarded your timing, as far as it could, you STILL had pinging. Your cylinders must have been getting flamed, bad.

Don't see how any of that could result in anything close to optimal mpg or power.

The only thing that I can think of is that when you have more power, then maybe you take advantage of that and drive the truck harder? When you have less power, then maybe you're worried about damage and are being more gentle with it?
 
Demo Man said:
I've been testing this theory. On my 3rd tank of 93. Getting ready to make a 650 mile trip from VA to ME. All highway. And not 95 either. Tolls are to high for me to pay.
Click to expand...

Awesome Awesome Awesome. Please let us know what you learn. I'm totally curious.


Be sure to use good reputable gas that is truly 93 octane.
 
Last edited:
Tacoma-Robert said:
I'm not questioning your word, or being sarcastic. Not at all. This fascinates me. But ... I don't see how that's possible.

If your engine was pinging, then it couldn't possibly have been running at optimal power. That means lower mpg, ceteris parabis.

Second, if it was pinging, then the computer retarded timing causing further loss of power. That means further lower mpg, ceteris parabis.

Third, even after the computer retarded your timing, as far as it could, you STILL had pinging. Your cylinders must have been getting flamed, bad.

Don't see how any of that could result in anything close to optimal mpg or power.

The only thing that I can think of is that when you have more power, then maybe you take advantage of that and drive the truck harder? When you have less power, then maybe you're worried about damage and are being more gentle with it?
Click to expand...

My pinging is happening at high load, low RPM situations like when climbing a hill with the AC on in a high gear. It isn't a constant pinging but I can hear a little. There is no change in power output when any of this happens. Others with pinging notice it in the same situations. An upshift or higher octane gets rid of it. Why does it happen? Not sure.

URD ran several dyno runs with 87 and 91 and found no power differences and no timing changes. You can always talk to Gadget about all this. Maybe elevation changes things but we will never know.
 
Last edited:
Ok. Here is the update for those who want to know. First tank was 19mpg. Second was 20mpg. This was not flat roads. Took hwy 81 thru PA to hwy 84 and on up. With all the hills it would kick down a gear when needed. Stayed at 72 mph on cruise till I hit the great state of MA. Then I had to kick it up to 80.
 
I currently have 1600 miles on my 2014 4x4 v6. About 90% of my driving is highway on flat roads while using cruise control at 70. Im still only averaging 15 mpg with 87 octane. Is this normal for tacomas with really low mileage?
 
A bit more but not much. I used to get 20 on stock tires driving mostly highway. I drive mostly street now and with the larger tires I see 15-16 all day.
 
Something doesn't add up with your MPGs. I don't worry too much about that stuff because I pay for the work I ask my equipment to perform. If your Tacoma is performing for you then that's the price you pay. Maybe you are hauling, towing, pushing, or dragging. She is doing work of some type.
 
Maybrook84 said:
I currently have 1600 miles on my 2014 4x4 v6. About 90% of my driving is highway on flat roads while using cruise control at 70. Im still only averaging 15 mpg with 87 octane. Is this normal for tacomas with really low mileage?
Click to expand...

15 mpg is ridiculously low.

I'm getting up to 22 mpg in my 4 cylinder 2013 4x4. I have trouble imagining that the 6 cyl would penalize so hard? Shouldn't matter that much on flat highway. Unless you modified something or are hauling something really wind resistant and/or heavy?

---
edit You might be running bad gas? I have run into that problem in the past. Check this out http://www.toptiergas.com/retailers.html
 
Last edited:
Well, guess what?

I have finished my experiment with running a few tanks of high quality gasoline in both 87 and 93 octane.

I will put the data together in a table to share here.

I find the results to be fascinating and compelling!
 
I have actually been wondering the same thing about mine, i mean i bought a truck, and i didnt expect 35 miles to the gallon or anything, but i wondered if putting a little higher octance in it, if it would improve on the gas mileage. I usually get about 18 or so around town and about 21 on the highway, but i do not have a lead foot anymore either. I believe i will try a few tanks of the 93 and just see if i can tell a difference, some good responses on here, so maybe i can put my .02 cents in and help the case some, lol
 
Vader said:
Here's something you might not know. I live in Canada and travel to the USA lots. When I buy the same 87oc in the USA I average 1-2 extra miles per gallon more then my Canadian gas? Why? I think it's the additives.
Click to expand...

Interesting... I live down here in NE Pennsylvania, when I travel up to White Lake, Ontario I fill up the tank for my 9.9 hp boat motor. I use 91 octane Canadian gas. I believe this gasoline does not have the ethanol??? Works will in my boat motor. I try not to fill the truck up in Canada due to $$$.
 
I have put a few tanks of 93 octane in my truck and its slowly getting better. It only has about 2200 miles on it right now though. The first two tank it was getting around 16.5 but this last fillup i notoced it was about 17.9 and i havent changed my driving any.
 
ecotecin said:
I have put a few tanks of 93 octane in my truck and its slowly getting better. It only has about 2200 miles on it right now though. The first two tank it was getting around 16.5 but this last fillup i notoced it was about 17.9 and i havent changed my driving any.
Click to expand...
I would say that's more the engine breaking in than the difference in fuel.
 
LUSETACO said:
I would say that's more the engine breaking in than the difference in fuel.
Click to expand...
Yea, but im going to run it for a while, and see what it does. I dont believe it can hirt anything. Maybe switch back once or twice to lower octane and see what it does.
 
You must log in or register to reply here.
Back
Top