ken_in_montreal

what octane rating should i use for 1.8tq?

A4MALITY˛(Joel)

at least 91 oct

Majorafro

Do you get 94 in your area? If so, use 94.

Audi Junkie

don't worry about the super. As long as it is not stop-and-go or for towing, you should get there on regs just fine. Altitude *reduces* the need for octane. Not a concern in Toronto, eh?

Levish

As long as you aren't pinging (pre-detonating) lower octane gas makes more power than higher octane gas

QuattroRocket

Nope 94 is everywhere in Canada too.

Audi Junkie

Not in California or many Western States.

QuattroRocket

Sorry meant in Canada not the US.

Audi Junkie

Brands matter and try to buy at a high-volume station, not old local-yokel tanks.

Flyin' SV

You should use the highest octane commonly available in the area you're traveling in. This is often called "Premium" or "Super Unleaded" here in the states.

You don't need to head off to the speed shop to buy 100+ octane race fuel, and you shouldn't need octane booster.

The available octane will vary depending on altitude, and sometimes due to local legislation. Don't worry about it, just buy the good stuff and drive.

In the event you have to burn cheap stuff, your engine will adjust the ignition timing to avoid harmful early detonation (or knock, or ping), and you may notice a coresponding decrease in performance.

91 at altitude is as correct as 94 is at sea level, and so forth.