'05 LGT Octane Question (not your typical, new weekly octane thread)...

[issai]

Car's in the Midwest where they use 92-93 octane. Most stations in Southern California provide 91 octane.

 

If I get the car and give it 91 octane, I shouldn't have any problems. Right?

[RedDragonV09]

Ive noticed that the fuel stations in the higher altitude areas tend to have 91 as Premium and lower elevations have 93, and in some places 94 and 97 (Ive seen it in Alabama offered as a step above Premium 94 no shit. It has a 4th nozzle on the tank.)

91 is the best I can get in Colorado and we are 6000+ I dont suppose you would have many problems running 91, You may get some pinging, you may not.

[itsme]

you shouldn't have any problems. If it is not tuned for higher octane the the ECU will adjust.

[issai]

Yeah, it's a stock car-- just wondering if the factory / dealerships would tune cars specifically for their regional gas's chemical composition. Sounds like not. Cool!

[Jacks GT]

I took my car from FL to MT in FL I would get 93/94 everytime I filled up, in MT I could only get 91, it felt a little different but no damage so you'll be fine.

[Cubby]

As long as the engine isn't knocking you can use any octane. Don't get me wrong, a stock LGT will likely knock on low grade, but the manual states premium and that means 91+. If you can get the "+" great, if not I wouldn't worry.

[Verwilderd]

The minimum for a turbo is 91 so you won't have any problems....really anything above 93 you won't see any gains. Here in Texas I have to use 93 because there is no 91, 87 is the next step down. But you won't have any problems with it. When subaru tunes these cars, they know what kinda gas the states use and tune accordingly. There are quite a few places in the US that only get 91 as their highest, so no worries there. If you ever find 93 you might see a slight gain over using 91 (if used consistently so that the car's ecu can adjust) but nothing too major. If they sell e85, go get some new injectors, fuel pump and tune and run that! You'll really notice a nice solid gain in performance and the fuel is cheaper than 85 octane.

[Timmay2]

Most computers can compensate for lower octane by pulling timing or modifying fuel tables. You will not get the best possible performance, but then again rarely is anything damaged using lower octane fuel. The computer can adjust in realtime provided all your sensors are doing their jobs.

[Verwilderd]

+1. Subaru states that 91 is recommended, but you can put a lower rating in. You will lose performance and it is not good to constantly put lower than 91 in. Plus, you can always get a lower rating and then an octane booster in and that should also work as well.

[fischer881]

+1. Subaru states that 91 is recommended, but you can put a lower rating in. You will lose performance and it is not good to constantly put lower than 91 in. Plus, you can always get a lower rating and then an octane booster in and that should also work as well.

 

I read in another octane forum about octane booster and if you have 87 octane pump gas and put in the 104+ octane booster it only goes up to about 87.4.

 

That is not a for sure but just something I remember from another for on this site.

[Cubby]

Octane boost is like $4-10 per bottle vs. the $0.20 difference in regular to premium. On a 15gal fill-up that's just $3. I'd rather get premium out right rather than mix anything.

[Verwilderd]

^^^If you can't get premium, then that would have to be the next best thing to do. That was to point of recommending it.

[issai]

Well I made it back. Chicago to LA in 3 days, with stops. I fueled up with 91-93 octane most of the time, but my brother insisted we pull off into one of those isolated small towns with nothing but 2 streets, with only 89 octane. As soon as the gas went down to the halfway point, I mixed in 91 octane into it. No knocks or pings or anything extraordinary during the whole trip

[Gasaraki]

The minimum for a turbo is 91 so you won't have any problems....really anything above 93 you won't see any gains. Here in Texas I have to use 93 because there is no 91, 87 is the next step down. But you won't have any problems with it. When subaru tunes these cars, they know what kinda gas the states use and tune accordingly. There are quite a few places in the US that only get 91 as their highest, so no worries there. If you ever find 93 you might see a slight gain over using 91 (if used consistently so that the car's ecu can adjust) but nothing too major. If they sell e85, go get some new injectors, fuel pump and tune and run that! You'll really notice a nice solid gain in performance and the fuel is cheaper than 85 octane.

 

That's just wrong... You don't get better performance from E85. You get a higher octane but you get LESS performance because ethanol has less energy than gasoline.

[fischer881]

^^^ If you get new injectors and a tune for E85 like Verwilderd said you will see a very decent gain in performance. Just hop over to the tuning section and look around. Alot of the guys over there mix it with meth too though.

[Verwilderd]

That's just wrong... You don't get better performance from E85. You get a higher octane but you get LESS performance because ethanol has less energy than gasoline.

 

You're dead wrong on that one buddy. E85 actually gives you quite a bit more power when coupled with the correct injectors, fuel pump and proper tune. It will allow you to advance the timing and get a more complete burn.

[itsme]

That's just wrong... You don't get better performance from E85. You get a higher octane but you get LESS performance because ethanol has less energy than gasoline.

Have you used e85? Just by being able to raise my timing 5 deg. with e85 I gained @30whp. You have to use 30% more fuel but, you will make more power.

[Verwilderd]

It's funny how wrong gasaraki is about e85.