i know nothing about this so i will not comment at all

but why does it say on our cars to use Regular Only?
is the engine tuned to that octane level....will it hurn in the long run to use higher???



confused

 

It won't hurt per se, but it won't do any good. Your car is set with a default timing advance, and can't go any farther than that. The times you want to be using higher octane gasses is when you need to avoid knock, (in cases of advanced timing--more power) and you guys just aren't running enough power. You can use higher octane, but your car will actually run a little worse, because the fuel is (according to the computer) burning incorrectly.

The thing with octane is that the higher you go, the slower (more efficiently) it burns. When you ignite the spark, the slower and more controlled the explosion is, the more power you can pull from it. Your engines aren't designed to pull power from the slower explosion, and are designed to take the faster burn of the lower octane. Putting in the higher octane fuels will make your ECU basically go "What the ****?!". So yeah. Unless you're running a turbo, save the money and dump in 87. But go 89 if you're feeling really kind to your car.

 

Its no so much a slower burn, just a more stable and predictable one. Higher octane is a preventative measure for pre-detonation, or knock. Running high octane in the regular Lancer is a waste of money and will foul your plugs quicker.

 

and plus, octane has this residual effect thing going on, if u dont burn the octane up it resides in ur gas tank.

best to be used in big power engine cars.

 

Residual octane?! Dude, where do you get this stuff!! Man, remind me to put this in my comedy routine. Octane is the rating of the gas, not any additive. If you have 94 octane in your tank, and put in 91, assuming half of each, you'll end up with something approximating 92.5 octane. It's not like stuff goes in to your cylinders and then whatever doesn't get used goes back in, I mean, god, if it was that easy, we'd never have to buy gas again!!

 

I also no nothing of this but what about lead content in the gas does a higher octane gas have less lead content? I have always heard higher octane is better.

 

Leaded gas (aka race gas) has a higher octane, however it is also killer to Catalytic converters. If you run leaded gas while you have your cat in, it will die, and your car will be spewing god knows what in to the atmosphere. While higher octane is good as a general rule, there's no point in putting in 94 octane in a car that was designed for 87/89. I mean, do you REALLY think that your engine needs the same gas as a porsche?

 

it says in my manual "Your vehicle is designed to operate on unleaded gasoline having a minimum octane rating of 87 [(MON+RON)/2], or 91 RON." So does this mean I am hurting my engine by using 91 octane gasoline? As far as the porsche statement goes I am only trying to take the best care possible of my engine I am not looking for more power from my fuel. I don't race and probably never will, I just want whats best for my car. Thanks alot for your input its greatly appreciated.

 

ok...these are some really usefull replies...good job graeme and everybody!


so are you saying that we should be putting 89 to keep the engine in better condition, but not 91 because there is no gain and it is not worth for the buck?

which is it ... 87 ... or 89?

 

I've always used Ultra 94 from sunoco....it provides better response.

That 89 octane stuff is for monkeys and hondas.

 

We don't even have sunoco out here I'm sure we've got a subsidiary/shell company [no pun intended]

IMO unless you need it, 94 is kind of a waste of money. My '93 talon isn't far from stock, so I still put 91 in it. Why waste money on gas when you could put it to mods?

 

so what is your final susggestion on a lancer?

i keep getting lost here

 

MY opinion is 87, and if you really feel like pampering your car, 89. Anything more is just pouring money down the drain for the "feel".

 

Thnx!

 

Have you ever compared a full tank of 94 octane to 91 octane? The response is much much better. Try it if you have a spare $40 around.