Although this topic has been discussed to death, it's interesting to see the poll....someone should create a new post titled POLL ONLY and put up the same gas poll
What octane do you run?
- Thread starter Gandy
- Start date
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I only run Top Teir 93 octane.
Are you guys who run cheap gas also going cheap on motor oil and filters? How about gear oil? Air filters?
Are you guys who run cheap gas also going cheap on motor oil and filters? How about gear oil? Air filters?
I think what we need is a "blind" MPG test.
Whos wife drives a LC? Dont tell her what gas youre using or anything else. Put gas in it for her, let her drive as normal.
Start with four tanks of 87 octane, average it out.
Then run four tanks of 93 octane, average it out.
Report back in a new thread with the miles per tank, MPG per tank and average MPG for the octane ran.
To make sure the results are as fair as possible use the same exact gas station and same exact pump every tank of gas.
Whos wife drives a LC? Dont tell her what gas youre using or anything else. Put gas in it for her, let her drive as normal.
Start with four tanks of 87 octane, average it out.
Then run four tanks of 93 octane, average it out.
Report back in a new thread with the miles per tank, MPG per tank and average MPG for the octane ran.
To make sure the results are as fair as possible use the same exact gas station and same exact pump every tank of gas.
The 87 I run is so great you don't even need motor oil.
87 here at (or below) sea level. When I go to Colorado or anything with altitude I switch to 91 just to offset thinner air.
Even the worst 87 you can get in the US is going to be better than what you find in 3rd world countries where LCs are more abundant and far more abused than here.
93
That is a good point!
I've been running 87 octane (8 tanks so far) since I bought the 2000 cruiser about 2 months ago. Never even considered running 91 yet. I constantly get 11-12mpg, but have gotten as little as 10.5ish; because of all the damn stop go in Houston. Next tank I will give 91 octane a try and see if I can feel/see the difference.
I've driven 1500+ miles in the last 22 days. I started at 87 pump for 2 or 3 tanks and then went 93. I drive in 330 mile chunks and I stop in the middle every time mostly the same place in La. 16.8mpg on 87 and 17.0mpg on 93. Straight driving, gas station to gas station to get some baselines, 70 or 71 mph on cruise. I've only filled this truck 4 times with stops in between to fill and check MPG. I didn't start checking until I got new tires, so all conditions were the same.
A better check In my mind would be paying up for the non ethanol gas that's outrageously more expensive. Bottom line I believe, it doesn't matter what you put in. Someone check the ethanol-no-ethanol mileage if you have time.
Fuel hasn't mattered for any auto I've owned lately.
6.3 Mercedes gets better mileage than a LC. 4.4 bmw also. I think that's sort of sad. Sad because domestics, and I'd throw in toyo and nissan with that category, can do better, and they choose not to. It's been like that for 20 years or more, so whatever
A better check In my mind would be paying up for the non ethanol gas that's outrageously more expensive. Bottom line I believe, it doesn't matter what you put in. Someone check the ethanol-no-ethanol mileage if you have time.
Fuel hasn't mattered for any auto I've owned lately.
6.3 Mercedes gets better mileage than a LC. 4.4 bmw also. I think that's sort of sad. Sad because domestics, and I'd throw in toyo and nissan with that category, can do better, and they choose not to. It's been like that for 20 years or more, so whatever
A Mercedes 6.3 in what? A G63 is supposed to get 12/14MPG. A 4.4 X5 M is supposed to get 14/19MPG. A LX570 is supposed to get 13/18MPG.
In a 5500-6000lb vehicle, with the aerodynamics of a brick, you're not going to get real competitive fuel economy, no matter what country it comes from.
There are almost no 3rd world countries where they drive gasoline/petrol 100's....
That's backwards. Higher altitude requires less octane. Combustion is slower at altitude due to less O2. If anything, run 91 at sea level and 87 above 4000 ft.
The X5 is lighter, has smaller displacement and better aerodynamics. Any G gets terrible mileage, because aerodynamics and weight.
I don't know a lot about engine design, but I find it interesting to note that high displacement engines with relatively low output tend to get worse mileage than higher output engines of the same displacement. This is something of a typical cliche attitude here in the EU about US cars (I am generalising). I think Jeremy Clarkson has repeatedly made jokes about this, how "Americans can get so little power from such huge engines". This is a broad and sweeping statement and obviously meant as a joke, but is there some truth to it? Perhaps this is also related to the bulletproofness of (among others) our 2UZ-FE engines. Big and strong but not a lot of work is demanded from them and thus they last longer because less wear&tear?
If there is no heavy knocking then go with the octane rating with least $ per mile cost. I have found in my tow vehicle, F250 with a 460, I go up a gasoline grade, from 87 to 89, when towing heavy loads or steep mountain driving.
E63 NA before the turbo.
Aerodynamics aside, the major 5 should be better than they are. I doubt there's anyone that doesn't believe the 4cy toyt should get better mpg, same with nissan vq. They might be outstanding engines but their mileage is piss poor. I'm generalizing, cars trucks, all of them. Of the 5k plus bricks I've had, the bmw and mercedes variety get better mileage. The idea is that I don't think gas grade matters much in the grand scheme of things.
Aerodynamics aside, the major 5 should be better than they are. I doubt there's anyone that doesn't believe the 4cy toyt should get better mpg, same with nissan vq. They might be outstanding engines but their mileage is piss poor. I'm generalizing, cars trucks, all of them. Of the 5k plus bricks I've had, the bmw and mercedes variety get better mileage. The idea is that I don't think gas grade matters much in the grand scheme of things.
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Apples to aircraft carriers.
You mean like a 2010 E63? It weighs 1500-2000lbs less, has much better aerodynamics, and has a tree hugging 13/20MPG on fuel economy, compared to a 2010 LX570 @ 12/18MPG.
You might as well compare that 2010 E63 to a 2010 C6 Corvette Z06 at 15/24MPG.
Your info on your travel, fill ups, different fuel grades, and observed MPG was interesting.
Your generalizations on comparing MPG across manufacturers seemed horribly flawed.
On a modern vehicle with knock sensors and the ECU controlling the timing, just about any fuel grade above 87 octane should work, with the exception of certain high performance models that are working with very high cylinder pressures either from compression or forced induction. The question is on those that can run 87 how much of a performance gap is there from retarding the timing a bit, in reality I agree, it's probably not that much.
These nontech threads are why we can't have nice things 
Depends on much more than the engine though, I mean the toyota yaris gets somewhere in the 31/41 range cty/hwy whereas the avalon gets somewhere in the 21/31 range
