a4rob

well thats complete bull.

Porsche made a big deal a few years ago saying how their cars, even their highest performance cars such as the gt2 and gt3 can run on any octane gas and that it will not damage the engine.

their cars, like most other companies are made to be driven around the world and to be driven in places that perhaps dont have 91 octane or higher.

adamstasiak

Yes this is what I say. Once my dad lived in Europe and he bought himself a FIAT. So when he was buying it they asked him what version do you want?
Finnish, Swedish, Polish, German?

I think they adjust to the country they sell to.

jordon

iTrader: (1)

i thought you have a 2.8 V6 adam... in that case, the octane is not nearly as important as with a turbocharged car.

adamstasiak

I have to undo my post. On the third day the car does not reach 6500 RPM. Mid grade is bad.
I am going to pour Octane Booster into it now.

petzl

What. No more nitromethane.

adamstasiak

Just a drop Added 30 ml plus a 100 ml acetone to get this ridicolous gas mileage 8l per 100 kliks

mikeh

What would we do without you Adam?

Stick to 91 octane, change your fluids regularly using the right fluids, drive responsibly and your car will last a very long time.

pablo_ottawa

Guys,

The octane number is just something to go by when you go get gas.

If your manual says put 91 octane in it then to do it. Why? Because at 91 octane the fuel ignites at the precise moment in the piston stroke that your engine is designed for. If your engine needs 91 octane and you put in 94, it may or may not take advantage of the higher quality fuel but it will still run to factory specs. It all depends on the ECU HOWEVER, I'd reckon that the ECU on an A4 1.8T will make the best of the higher octane and use it to run the engine more efficiently.

That said there are things called Knock sensors. All late model engines have them and the 1.8T is no exception. The knock sensor is there to sense any "knocks" it hears in the engine. This info is passed to the ECU which adjusts the ignition timing to compensate for any "knocks" thereby making the engine run smoother. So if you put 87 octane into and engine that is designed to run using 91, the ECU will compensate for the added knocking that a lower grade fuel (87 vs 91 octane) creates.

Now that being said, there must be a good reason the manual is telling you to put 91 octane in the engine and I'm pretty sure it's not just to make you spend more money on gas. for me, I just do it and pay the extra 4 bucks per fill up. Really, WHO CARES!

adamstasiak

Yes this market became very accomodating. I can get used tranny or engine from Los Angeles for 2000 bucks. Ha ha Go figure

MattRaczka

Mikeh "Octane levels have nothing to do with gas mileage. We have beaten this one to death on other threads." 100% agree
87 octans just killing faster u turbo.