+1 for 87

it gets better MPG! haha

 

-to the guy who said the manual says 87 octane.. my manual says we have 3 cats. anyway 87 ftw.

 

87 non-arco ftw!

 

meh... 87 all the way... 31+mpg highway going 70-75mph with the 2nd to lowest setting on A/C or sometimes just the lowest setting. and this is on summer mid day times.

 

i've seen plenty of tests done on different grades of gas and here was the consensus:

1. if your engine is designed for 87, use 87; anything higher does NOTHING....only waste MONEY

2. if your engine is designed for 91+ (premium), use 91+ or it will lose performance and gas mileage

3. using lower grade fuel in a car that recommends premium will not cause the engine to break down any faster than using premium; it will only cause a decrease in performance and gas mileage.

our Tc's engine is not a high compression engine....not by the widest of margins. you want high compression engines, look at honda's. toyota products have never been known for high compression engines.

 

i've been using 98 octane in my N/A car

 

NOT true. Even in modern engines with knock sensors, if you put 87 in a car with a 12:1 compression ratio, you will eventually get knocking... and knocking KILLS engines.

 

Just encase anyone wanted a 2nd or 3rd opinion, Car Talk has tackled this answer so many times that they put up a nice piece about it on their website:

http://www.cartalk.com/content/featu...questions.html

And I thought Yahoo Answers was ok, but those guys were awful! Just goes to show you that not everything on the internet is true.

 

>> drax... setting morons right for several years now*




*He is correct, 87's good; he read 'it could be argued..' & he did.

 

ok get the point everyone.

87 octane if your N/A or its a waste of your money.
91 octane if your boosted.

done and over with. lolz.

 

meth injection.
F.T.W.
lol

 

better go do some more research.

 

87 vs 89 vs 93 will not do anything in our engine. But the residue left behind by the 87 can collect in the cat and eventually cause it to clog. This usually takes a very long time to happen though. Happened to me around 170k. I have heard to the tC's having crappy cats though. So if you plan on keeping your car for 8,9, maybe 10 years you can either run 89 or just have some money around for a new cat.

Or you could just get rid of the cats and put an antifouler on the 02 sensor.

 

what? how does 87octane leave behind residue?

 

i have always thought that higher octane needed a hotter spark to burn ... cause of the octane level in it... if your computer is preprogramed to burn at a lower heat then u would need a lower octane since its programed.. thats the way i figured it worked.. when i would fork a couple hundred on a power pragramer ..thats what i fig was the diff in the programming,,, it would tell the computer to run lean and generate more heat to combust more fuel,, so then u could burn higher grade fuel and get more power...does that make any sense to anyone

 

the tc has a LOW compression motor and only needs 87 (unless your are running a supercharger, turbo or nitrous)


you obviously don't know what you are talking about.

 

Man this is just a field day for all the morons out there isn't it... no offense people... but here's the truth:

91 octane is NOT ANY CLEANER THAN 87!!!!!!!!! 87 WILL NOT CLOG ANYTHING, CONTAMINATE ANYTHING, OR CAUSE YOUR ENGINE TO BLOW UP OR CLOG AFTER 80,000 MILES! (sorry for caps lock )

A gallon of 87 octane has about the same amount of potential chemical energy as 91... which means you will not see an increase in gas mileage or power if you top up with 91.

The ONLY difference between 87 and 91 is 91's resistance to pre-ignition. Octane number has NOTHING to do with energy content. Yes it does require a hot spark to light up 91, but you'd be hard pressed to find a spark plug that won't. And once the fuel starts burning, it's a self sustaining reaction as long as there's oxygen in the cylinder. That goes for ANY kind of fuel.

Putting in 91 will not make the flame burn slower or anything causing more complete combustion or more energy to be absorbed by the piston. The same amount of energy is released no matter what grade fuel you use, and the piston absorbs an equivalent amount of energy...

You would only need high octane fuel if your engine runs a high compression ratio (higher than 10:1). Reason being is that when air is compressed, it heats up (diesel engines work on this premise, they don't even have spark plugs). If there is enough heat from that compression to start a reaction before the engine was supposed to spark, you get detonation (pinging, knocking, whatever). Same thing goes with Forced Induction. You are forcing more air into the cylinder, and thus more air ends up being compressed... which is why you must use high octane to prevent knock...

Any more questions?

 

 

Actually, it will run very differently on race gas (100+ octane). It will run like absolute ____.

 

^^but if you are like vader then you wouldn't even need gas.. just use the force.. hahaha