What octane are u running ?

At that price your getting 75% goat piss added.

 

As fate would have it, my truck runs great on goat piss. Drove over 90 miles today, including some bumper to bumper traffic, and it is averaging 26mpg on the $1.86 gas.

 

OVtune requires higher octane or is that an option based on the level of tune?

 

I really could not tell you because I never have bought any 93 octane with Ethanol.

 

"here in the mountains than with our crappy regular (85 or 86) at 6500' elevation"

85 octane at 6500 feet is not crappy. It's exactly what you need. You have thinner air and lower compression at altitude and simply don't need the "normal" 87 octane. In effect, the the equivalent due to the elevation.

 

Option based on chosen tune. You’ll get better performance with the higher octane versions of tune but it’s not necessary to get the bulk of the benefits.

 

Sorry, for those members that claim they are getting better gas mileage with higher octane is BS!

Modern electronics in our vehicles play a major role in the regulation of fuel consumption. Believing that a higher octane in our truck will improve fuel efficiency is marketing nonsense. At best wishful thinking.

 

Agreed. All believers, read this and report back your findings. All octane does is reduce the ignition point of the fuel, making it less likely to pre ignite before the combustion stroke in a high compression engine.

http://yourcarangel.com/2015/01/myth-high-octane-fuel/

 

You that's what most says but a few of us experienced otherwise.it just Runs smoother and no pings on acceleration. For me it's worth it.

 

That perspective was relevant back in the day of the carburetor and early fuel-injection, but not anymore e.g. https://www.usatoday.com/story/mone...gasoline-low-octane-too-much-ethanol/2369579/

All I can say is, my engine (a 2GR-FKS) sounds and drives very different at 6500' with 88 octane versus 86 octane.

 

Sorry if I don't find your car angel as a credible source. There are a few basic facts about our engines, physics, and mechanical engineering that would suggest higher octane fuel would be beneficial, at least from a driveability aspect.

Fact 1: Our engines run at 11.8:1 compression, which is pretty well up there. Higher compression engines generally perform better with higher octane fuel.

Fact 2: Our engines have variable valve timing. With a high compression motor not receiving higher octane fuel, it must compensate by reducing timing. From a ME standpoint, this is an inneffeciency, likely resulting in a loss.

Fact 3: With higher octane fuel, holding the ignition point in relation to optimal timing, as designed by Toyota engineers, will result in optimum efficiency.

Will you get better gas mileage? Probably not as you are trading horsepower for economy. But you are assuredly increasing efficiency, and keeping an engine from lugging along due to mechanical inefficiency, which in my experience is the case, it is possible to see modest gains.

That's science...

 

I've been putting premium in it because the truck seems to run better on it, it feels like it struggles more with lower octane gas. I'd run regular gas if I had the OV tune for 87 octane but for me, my truck runs best on 93 with the factory tune. These 3.5 engines are damn near 12:1 compression, I would expect them to favor higher octane. I'd love to try some ethanol-free 87 for comparison though, just never seen it around.

 

Regarding higher octane fuel producing better fuel ecomony: https://en.wikipedia.org/wiki/Placebo

Show us your data.

The truth is if higher octane fuel produced better fuel economy, manufacturers would suggest we use it.

 

The end of the article clearly points out that high compression motors benefit from higher octane fuel. Those are my findings.

 

But when you're running 11.5:1 comp or higher and locked out timing you need higher octane fuel

 

You mean right before it says "To know which gas your engine is designed for you should consult your owner’s manual."?

Static compression ratio is only part of the equation.

 

No they wouldn't. They would try like hell to get their engine to run on the cheapest fuel possible to lower total ownership costs. By law, they are required to post fuel economy data and projected fuel costs. One MPG isn't a big deal compared to the price difference between regular and premium multiplied by every single gallon you pump into your truck every year. That's about as basic as math gets.

Part of the reason that dual vvti exists is to allow a higher compression engine to run on lower octane fuel. Perfect example was the 07-09 FJ Cruiser, which required 91 octane premium fuel (with a Tacoma motor). In 2010, they dropped in the dual vvti 4runner engine, and wouldn't you know, they lowered the requirement to 87.

https://www.fueleconomy.gov/feg/Find.do?action=bt1

 

Yeah... Check my earlier post. I cover more than compression ratio.

 

Fact 1 - Almost no one looks at the total cost of fuel number on the sticker. The number of people that buy cars that require premium, but don't realize it until after purchase, is not trivial. e.g. Mini Cooper S or Toyota 86.

Fact 2 - If premium fuel results in increased efficiency as you claim, that would have to manifest itself in increased fuel economy. You can say physics and mechanical engineering all day, but you cannot argue with increased engine efficiency = increased fuel efficiency.

If premium results in better fuel economy, surely someone can post real data. I'm currently getting well over 23 mpg with "goat piss" 87 octane and an automatic in a stock Limited.

 

Your first point isn't a fact; it's an opinion about car buyers' habits and their overlooking vital fuel information listed on the sticker.

Secondly, I clearly stated that while the engine may be running more efficiently, the trade off is making more horsepower, which has a negative effect on economy. Efficiency does not necessarily equal economy.

My anecdotal evidence is this: my engine runs better with premium fuel. It allows other components on my truck to perform their jobs more effectively. The sum of these effeciencies equals a better driving experience and enhanced driveability. An increase in mileage could exist, but I'm not here to make that argument.