Your exactly correct also i would add as for mentioned many times in this forumn, these cars are not sports cars, regardless if you think your a big dog who constantly pushing your ls to its limit, i would argue thats not what these cars were designed for. Easy answer this little .v8 has knock sensors whos main purpose in life is to prevent damage and retard the engine when and if it detects conditions like lower 87 octane, although 87 is listed in my ownwrs guide as usable fuel. So the whole point may be mute man let the guy enjoy saving money,

 

The guy who bought the nice HDTV and doesn't pay for HD content from his cable provider is "saving money" too.

It's possible to "save money" but actually extract less value of something.

 

LOL i saw you on the guys got cable comercial. But really we were talking about engines and octane not the size of your tv screen or how many channels you have. With that i bow out you you re the winner.

 

That's all well and good and I agree that this is not a sports car however Toyota has specifically noted that using octane lower then 91 may cause knock. We can argue about the conditions where this can happen or not happen but that is an unknown. If Toyota listed the apropreate conditions that would be fine but since they don't it should be assumed that it can cause damage.

 

It's called an analogy. You're paying more for a premium car that performs in a premium way. Reducing the quality of its performance mah save you money, but that doesn't mean you're getting a better value.

 

Get a good gas card. PenFed has a 5% cash back (not points, cash) with no limit on gas purchases. At typical pump prices of over $2/gal (Nov 2015), that's 10 cents a gallon off free for nothing.

 

That's actually a pretty good idea...

 

Just got through optimizing all our cards. 5% gas, 5% Amazon, 4.75% groceries, 2% everything else. All cash, no points. All cards set to autopay full balance from checking account. Debit card destroyed. I figure if you're going to spend it anyway (and you ARE), might as well get the biggest discount possible.

 

Use 91 octane or higher. It's the recommended gas for our car.
If you want to save on gas don't floor the gas pedal and make sure the tires are properly inflated.

 

Going through the thread, just a few tidbits that I found interesting no one had mentioned earlier:

- All cars nowadays have a knock-detection feature that retards timing. Generally this is for use in other markets where the availability of 92 octane and above fuel is non-existent. Therefore, laws determined that in order for a vehicle to be sold in a certain country, they must conform to be able to operate at 87/89 octane where this is the only fuel present - thus trickling the effects down instead of increasing production costs of multiple variants with/without this feature.

- It's almost entirely passed over that using lower octane on high compression engines may actually increase cylinder head temps drastically, especially during prolonged high load intervals. This is well-known in the force-inducted community and makes no difference here. When your engine starts hesitating due to the retarded timing and fuel cutoff, it is trying to save itself but cannot dissipate the heat well because fuel is the first and main thing that is used to regulate/cool the combustion chamber. When that shuts off, the coolant/oil can only do so much until the fuel is sprayed back in there. Now think of that vicious cycle repeating and you get the idea.

 

Would you be able to provide a link to the "law" you are refereeing to in first paragraph.

"This is well-known in the force-inducted community and makes no difference here."
It makes a huge difference, actually it is the major difference. With forced induction, commonly know as turbocharged engine will create higher compression ratio which can easily detonate.

You are also mistaken on fuel being cutoff IF necessary ECU will add more fuel because it is much more difficult to detonate rich mixture.

Basics from turbocharged communities:

In order to reduce the probability of knock at full load on a turbocharged engine: 1) reduce boost, 2) adjust the Air-Fuel-Ratio to richer mixture, 3) retard ignition timing.

 

Excellent post. As a person who has dabbled in engine tuning this couldn't be more true. Once cylinder temperatures are exceeded then it becomes a cascading effect that is outside the normal parameters of the engine. Bottom line is high compression is still high compression and requires premium fuel. If you have to depend on the technology to offset knock by retarding timing then you're not doing it right.
I think what Toyota as well as other manufacturers have done is allow people to use 87 in a pinch for those people abroad that travel between countries were premium is not available. I do not think it was ever intended for economy.

 

There's two topics on this forum that I have learned to stay away from, whether to change your transmission fluid and whether to use 87 or 91/93 octane gasoline. And so I will.

I am only chiming in to add to the gas card discussion. A while back I got a Shell Fuel Rewards card. It's free and it is not a credit card. You scan it into the pump and then scan your credit card. It lowers the per gallon price on the pump by at least 3 cents per gallon, but sometimes I get 10 cents and once I got 50 cents off per gallon (maximum 20 gallons).

I don't pay enough attention to it to tell you why the discount varies, and I think you can get other dining discounts as well.

 

Toyota Land Cruiser, Sequoya and Tundra are all using exactly same engine. Guess which fuel type is required?

 

Those do not use the -FSE variant which incorporates direct injection.