4-Bangers and octane

Have to disagree with you brother they are not the same.

 

I run the best fuel I can purchase in my area which is 91 octane, 93's not available and 87 and 89 have 10% ethanol which is horrible for mileage. I have used Shell fuel in the past and really like the product. The wife's old F150 liked the Shell 93 when I could get it during long road trips. The extra money for 93 isn't so much for the octane but the detergent packages, the higher the octane the higher concentration of detergents.

 

Blah blah let's f,ing argue some more about this. You like it, its your truck , run whatever makes you feel good. This argument will go back and forth without any more solid, proven conclusive evidence. want to end the arguement, hook it up, run it on a dyno with everything the same for a tank of each and then report back.

 

whats the matter, you dont want to keep running around in circles with this. I agree with you !!!!

 

In a given car it may run worse , but what proof makes it fact that it runs worse?? There is ample proof that it preforms BETTER, in some vehicles.
92,87 ,89 its an expression of octane molecule ratio to other molecules. In others words 8 basic components linked together rathar than 7 (heptane if i recall.) Octane molecule resists detonation better. Engine tuning determines performance not so much the fuel , the fuel allows for more timing and increased performancefrom the engine. You see that gain in performance in hot rods , older v-8s mostly.
All that and the 2.7 isnt even in the mix yet. It really isnt. I tried 89 octane over 87 here, you know , to prove it doesnt matter. Maybe it still doesnt , but my truck ran a bit smoother, couldnt tell if it had more mpg or power though.

Bottom line , the 2.7L is recomended to run on 87 , i doubt it can take any real advantage of higher octane. If it did , what will it gain? 1hp on a perfect day at a dyno? It wont get you to work quicker , or make u a better driver , nor will it add to engine reliability. It will make your wallet a bit thinner in the long run.

 

i have a feeling this thread will continue forever

 

guys as per the manual that toyota supplies with the 2011 tacoma on the very last page it states under fuel recomendations 87 Octane or Higher I dont know why its so hard for everyone to understand that. If the engine was designed to function only on 87 octaine then the manual would state USE 87 OCTAINE ONLY.

 

OK. Where does it say improved performance or better fuel economy? .

 

you're kidding me right.

 

Im officially done with this post. You guys are either all mental or cheap.

 

I use 87

http://www.exxon.com/USA-English/GFM/fuels_quality_gas_faq.aspx

 

"Are you tempted to buy a high octane gasoline for your car because you want to improve its performance? If so, take note: the recommended gasoline for most cars is regular octane. In fact, in most cases, using a higher octane gasoline than your owner's manual recommends offers absolutely no benefit. It won't make your car perform better, go faster, get better mileage or run cleaner. Your best bet: listen to your owner's manual."

http://www.ftc.gov/bcp/edu/pubs/consumer/autos/aut12.shtm

 

....like i said I doubt it would show more. ( i think i messed the quote up though)
If a person wants to run 91 octane then they ought to buy a sports car that runs on it. 91 octane or more octane in general seems like buying a corolla and asking if it'll offroad with mud terrains.
Last car i had to run higher octane was a 83 impala, it would ignite fuel when turned off on 87 , 89 seldom did it so i bought it ,also i could actually adjust the timing at the distributer( remember those? I still have the wrench too!)...91 made sense. Those days are gone the way of the crank start and buggy whips far as me and my tacoma go. Go 87 and be happy for 1 less thingto worry and waste time with.

 

Haha. Awesome Thread! Just read the whole thing. . . Late to the party again, as usual but thought I'd put my .02 in.

Although, it's probably going to be boring compared to the awesome posts previously. . .

The way I took what the 2011 owners manual said is:

Use 89 Octane or Higher. . .BUT - Research 91 or higher.

What do I know - I started out running 87 and then switched to 89. I noticed my mileage improve a bit but I'm starting to think that's because my engine was breaking in.

I think I'm going back to try 87 and check my MPGs. . .makes sense that 87 would be fine - especially with the way gas prices are headed - they ain't going down. . .

Great thread guys.

 

you can't hear him you silly goose

Forum/Facebook fights are the best!

 

INCORRECT. Higher octane resists detonation. Yes a turbo needs higher octane, but its not MADE for turbo motors. My last engine was a K20 out of a Civic SI. redlined at 8000rpm, and had a compression ration of close to 11:1. I had to use higher octane to have it run the best, and there was no turbo.
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After jumping into this thread late I apologize, but "Tepidy" obviously isnt pulling shit out of his ass and he feels a difference with the higher octane gas, and its true because you WILL notice a difference. Often people recommend higher octane to help make a motor run better as well. Anything that's working under compression would gain from higher levels of octane. Its just common sense. They made the gas for a reason. I use 87 octane right now only because Im poor as a joke this month (4th/final year of trade school and EI is fucking me over again) but as soon as Im back to work 91 octane is the highest we have and I will be running that. Its WAY cleaner then the other gases, and usually on Thursdays Shell has it cheaper and it works out to only be a few bucks more per fill up. Shell ALSO has the nitrogen enriched gas which will clearly keep your cylinders cleaner over the run of its life.
Thats not just my "2 cents", its just the basic facts of a combustion engine. Higher octane is obviously a better choice, but not necessary, but really........why not spend a few bucks more on something your putting 30-40k into?

 

I gained 3 mpg by going from 91 to 87. No decrease in performance noticed either

 

Shell is just trying to trick stupid people to buy their gas. Keep using shell 91. The 2.7 GAINS nothing for using anything higher than 87.

 

except a cleaner engine which was that guy's main point.

 

exactly. I would gladly give .25-.5 mpg for a cleaner engine. Shell cant "trick" the basic fundamentals of chemistry. If they add nitrogen like they say it will help