Top Tier Gasoline

Currently a misconception, but it wasn't always the case (with a qualifier).

Old school... carbs, conventional ignition systems with only centrifical and vacuum advance.... Prior to the mid-late 70s it was possible to run the ignition advanced beyond manufacturer's specs, and you could get away with it by running premium.

Once computers took over, there became very little that we could do.
On some GM models as late as 1995, it was possible to bump the static advance by a few degrees... it was good until you needed a smog check and then you had to return it to spec. I'm pretty sure the Vortec put an end to that.

 

Not true. ECU adjusts timing based on feedback from a number of sensors. More than one of the track guys (Super Werty, maybe?) have recorded increased timing allowed in the 1GR-FE after consistent 91/93 octane usage.

"losing" power in the sense that the engine will not peak as high with HP and Torque on 87 compared with 91 or 93. However, most of use don't run our vehicles anywhere near peak engine output, so in terms of daily driving there's little to no meaningful difference.

I can see the difference mattering in situations where the engine is under strain: towing, offroading, hauling, track days.

Except that the 1GR-FE was designed to run on 91 octane and has computer safeguards in place allowing it to downgrade to 87 safely:

http://en.wikipedia.org/wiki/Toyota_GR_engine

Note the higher peak outputs on 91 octane fuel. This is how the engine is rated in testing by Lexus.

"But wait" many people say "The list of applications doesn't include a Lexus vehicle!"

True, but it does include the Land Cruiser Prado 120, which is simply rebadged and sold as the Lexus GX470 in the States (albeit with a different motor, not that this matters: Lexus spec'd both engines during the design process).

(in fact, the 120 platform is what our Tacomas, the FJ Cruiser, the LC Prado, and 4th Gen 4Runners are all based on. This is why many parts are interchangeable from all these vehicles).


To summarize:

Premium octane fuel will give you higher peak numbers on the Dyno, and maybe make your truck happier when its working its hardest. It won't change the daily driving experience.


BUT:

None of that has shit to do with the topic posted in the OP, which is top tier gas, which is a "certification" of sorts for a gasoline brand which declares that gas has a certain volume of engine-cleaning detergents.

FWIW, I use top tier 93 octane gas in my Taco. But then, I don't drive it daily, and I use it hard when I do.

There, I've contributed to the thread. I feel good inside.

 

maybe not in your newer truck but it is definately noticeable in my 3.4
there's a difference in throttle response for sure.

 

I have no idea how 1st gen motors relate to different octane grades. Haven't researched it because I don't own one.

I'm gonna argue placebo effect until you can get me a source though. I never trust butt dynos.

 

How does 93 octane gasoline make a inanimate object "happy"?

 

Back to the original issue about top tier fuels containing more cleaning additives. I burn Chevron and Texaco religiously (both are listed as top tier) and still have add fuel injector cleaner once a month to all three of my vehicles. SO I can onlt imagine how bad the non top tier fuels are. And yes it makes a difference and yes you can tell 1/2 way through a tank with injector cleaner in it. On the octane issue in newer vehicles if your vehicle is not chipped and/or the computer programed for premium, you are wasting money and losing power.

 

http://www.tacomaworld.com/forum/2nd-gen-tacomas/36847-gas-octane.html

page 12 post 232-jandrews
page 13 post 243-jandrews
page 15 post 288-jandrews
page 15 post 296-jandrews
page 21 post 403-jandrews
page 21 post 405-jandrews


placebo huh?
looks like I'm not alone here?
my truck on 87 feels like I let 10lbs of air out of all my tires. That is a fact. Looks like YOU experienced the same thing in yours AND you were pretty adimate about it. WTH?
Too bad that tsunami didn't take me out huh

 

I always try and run shell or chevron 91 and will go out of my way just a little to get it. Does it make a difference, who knows. I am just willing to pay an extra 10-20 cents a gallon to put in a "top tier" gas. I don't put more than a hundred miles on my truck in a week. I was bummed the last time I filled up at my favorite local shell gas station, for years they sold non ethanol gas and now, 10 percent ethanol

Next time I fill up it will be at the local sinclair, they still sell straight gas. I guess it's not about the brand name for me, I fill up where they sell regular old gas, while I still can.

 

From what I've read, the only fuel additives that are really effective are ones that contain PEA. Techron is basically Chevron's patent name for PEA (I believe they invented it). The fuel cleaner additive bottles at the store are generally ineffective unless they contain PEA. The last I knew, the only ones that contained PEA were Techron, Gumout Regane, and I think Shell's bottle of additive. The rest is largely snake oil.

I think the only other company that uses that sort of additive is Shell. I read at one point that they only use it in their premium grade, whereas Chevron uses it in all grades.

We often buy generic fuel for the vehicles, and I run Techron through them periodically. The car loves itself a bottle of Techron; it usually increases the mileage a few points while it's in there.

Mostly, I just try to avoid sketchy-looking gas stations. If they aren't maintained, then you can have some issues, otherwise federal standards should keep the fuel OK.

 

How does one inanimate object "love" another inanimate object?

 

Have you seen the new Mazda3? It's got a gigantic-ass grin across it's whole front. It loves everything, especially Techron.

 

my 2gen v6 4.0 is the same way. 87 makes it little sluggish. In fact yesterday I decided to go cheap since gas station had 93 for 4.45 per gallon so I got 87 instead. Well today on my way to work scanguagae clocked 3+ mpg less. That always happens when I get 87 . there is few MPG drop and I can barely stay above 20MPG. If I get Shell 93 truck gets 24-25 MPG on exact same route.

 

I'm going to have to try running premium fuel again. I've tried it before, and didn't see any improvement. We were on a road trip, so it was all highway miles. Maybe I got a bad batch.

Best mileage was as I stated before, consistent 45MPH across a couple of tanks full. I think that was with 85 octane, as that's what you see most in Wyoming.

Elevation greatly impacts fuel grade, so maybe that's why some people see a large increase in using higher grades. Maybe?

 

Did you actually read those posts at all?

All I stated in any of them is that Toyota has tested and confirmed different power outputs for the 1GR engine with different octane levels. Essentially the same thing I've been saying in this thread all along.

Please tell me what that has to do at ALL with the 1st gen engines?

http://www.youtube.com/watch?v=G2y8Sx4B2Sk

 

It takes at least 4 or 5 tanks and a few weeks for the ECU to adjust. Octane isn't the only factor in the equation - information from other sensors plays a role.

 

Ah, that makes sense. It's probably near $.50 a gallon more than regular though. Has anyone done the math? That's about $10 a tank difference, I think. I guess, if it saves you even 3-4 gallons of fuel, you'd at least break even.

I've been using Sta-bil a lot lately as I'm not driving the truck as much right now. I haven't noticed anything, but I wonder if that would have any effect on mileage. Only used it a couple tanks now.

 

I think you guys are just fooling yer selves. Gasoline, no matter what the brand, comes from the same local distributors. Do different brands really put in more additives? Doesn't a "top tier" price really mean a station is closer to a freeway exit? I've been using what ever comes out of the base gas station for 16 years without ANY fuel system problems. Octane is just an anti-knock measurement and my engine doesn't knock on regular grade, so I'm not gonna' pay more for no reason. I did ask my truck if it was "happy", but it didn't answer me.

 

Air craft engines run high test to keep them from detonating they are air cooled and run lean, when you shut them off you lean them out (they have manual mixture control) till they no longer have any thing to burn no fuel they can't run on. High test has less heat energy then 87 it's only needed only in high performance and forced induction cars (and air planes). Think what you want it's your money and there is a lot of snake oil out there to try to separate you from it.

 

Yep. All the gas comes from the same place, and additive is in injected at a rate of around 1 gallon per 1000-5000 gallons of gas.

But by god if it makes you feel better to buy a certain brand, have at it.

 

Which additive is the question. Top Tier (and BP's "invigorate" blend) ensure I'm getting enough of the stuff I want; namely, a certain level of detergent.