Premium Fuel???

I just purchased a 2005 Legacy GT, and for the first time when I filled up with gas I noticed a sticker which says to only use Premium unleaded. Since Gas is so expensive, I used 87 octane. Does anyone know what kind of problems down the road that may occur if I keep using the cheap stuff.

 

Thanks in advance.

 

Jason

lots.

I just purchased a 2005 Legacy GT ... Since Gas is so expensive ...

 

The mind boggles.

Can you be a little more specific. I could understand the performance may be affected.

sigh....use premium, that's why it says it on the fuel door.

there is no reason to be more specific...you bought a car that says use premium...so use premium. you aren't saving yourself a whole lot of money by using regular.

The car has a high compression engine and requires high octane fuel.

 

The warning sticker is there for a reason.

That makes sense. Thanks

Some cars say premium fuel recommended for best performance, such is the case with the Subaru 3.0L. Subaru says premium is required for the 2.5L turbo. There's a difference in the language.

 

Long-term use of 87 octane is like going to a track day with corded and plugged tires when you have a new set of tires at home, but you are too cheap to get mounted. Why spend money on a track day and risk such a huge negative when doing the right way costs so little?

Welcome to the forums... JROTES....

Im assuming you have a newer car...maybe 08?

I believe in 06 it was recommended to use premium but not really required.

However, I have an access port and have tuned the car to run on PREMIUM only so I don't even worry about it.... always premium...always high quality gas like chevron.

 

If you hear pinging or knocking (pre-detonation) octane boost or change to premium right away. That can cause you big problems.

 

You bought a performance car .... and it isn't a cheap car so don't go cheap on the gas.

 

20 cents per gallon comes out to just about 3.00 more on an FULL fill up.

$3.00 you save isn't worth the lack of performance or problems you will face by skimping.

 

If you are filling up every day and the $3.00 adds up quickly then you should have bought a hybrid..

 

have fun!

You can always trade it in for a Legacy 2.5i. You can use 87 fuel AND you get better gas mileage too. It'll save you money on the long run.

Welcome to the forums... JROTES....

Im assuming you have a newer car...maybe 08?

 

 

I just purchased a 2005 Legacy GT,

 

 

but yeah. It's not that much more for premium

better than the '08 STI which requires 91 but 93 is recommended.. especially if you're in a state where you can't get 93

but yeah. It's not that much more for premium

better than the '08 STI which requires 91 but 93 is recommended.. especially if you're in a state where you can't get 93

do people even read the stickies???? honestly, do a search

 

and yes, it will suck when I buy my 08 STI because we only have 90 octane. That is why I use Torco... so it won't matter.

You can use 87 when premium is not available, the computer detects pinging (not good sign) and reduces boost and retards timing. The engine makes less power but if pinging still occurs it damages engine. Sooo

If you want to use cheap stuff you bought wrong car, if mpg and fuel cost is that important 2.5i would have served you better.

 

Krzys

Welcome jrotes! Definitely only run premium in the GT. It says Premium fuel ONLY on the gas cap door. It would be like seeing a sticker that says Diesel fuel ONLY on the door and putting gasoline instead. Although I admit on a diesel the damn thing wouldn't even run, but try to picture it like that. 87 octane will cause severe knock and cause the car to go into safe mode and kill your power. Spend the extra 3 bucks and get super. ALWAYS.

 

BTW fonts, the LGT doesn't have a high compression motor, it has a low compression motor with a turbo that compresses the incoming air. The only turbo cars that get away with a moderate amount of compression right now are Direct injection cars like the Mazdaspeed 3/6.

In florida you could get 93 anywhere now im in montana you can only get 91 its still wickedly fast but i can feel the difference. But im happy coz now i can go fast and round bends unlike FL.

Back on course do as the sticker says! It is there for a reason. If you drive sensibly you can still get 28mpg+. It will be cheaper in the end my friend so do as the sticker says.

do people even read the stickies???? honestly, do a search

 

and yes, it will suck when I buy my 08 STI because we only have 90 octane. That is why I use Torco... so it won't matter.

 

Hope, do you really only get 90 in Alaska??? I thought the crappiest gas was in Cali! That's just blasphemy!!

Jrotes: in light of what you did, it would be helpful if you answered some questions for us:

 

1. is this your first turbo car/high performance car? first car that required premium fuel?

 

2. why did you buy the LGT, was it a well-informed deliberate purchase? are you a long time subaru fan? did you cross shop and find it met your needs? do you like sports sedans?

 

3. what is your driving style? daily commuter moderate? fast and aggressive? very casual and slow?

 

I ask these questions because based on your original post, I'm not sure why you chose this car if you wanted to cheap out on the fuel requirements. Seeing as how there is usually a $.20 price diff between 87 and 91/93 octane, you are saving at the most....$3-4 per fillup?

 

Hope, do you really only get 90 in Alaska??? I thought the crappiest gas was in Cali! That's just blasphemy!!

 

Agreed, that really sucks, how ironic that Alaska, being the state with that damn pipeline and having all those natural oil reserves...be the state with the crappiest end product. Is the low octane some cold weather engine measure?

 

is that meager effort in money saving really worth the potential damage to your engine if you want to make this a habit?

Hope, do you really only get 90 in Alaska??? I thought the crappiest gas was in Cali! That's just blasphemy!!

trust me.... we scream about it because it's crap. however, from what I'm told, we don't actually refine the crude oil here, just drill it, produce it and send it on it's way. I believe most of it is actually refined in CA (go figure). Seems pretty stupid we are one of the largest oil fields however we only get the craptacular 90 octane gas!

Better answer. You will get worse gas mileage with 87 octane. Probably more than 30 miles to a tank worse. Paying the extra $3 a tank to fill it with premuim will get you those 30ish miles(~1 gallon worth) back and pay for it's self. You can pay less at the pump per fill and get lower gas milage and lowered performance or you can pay $3 more and get higher milage and better performance; thus breaking even over the long run. Not to mention; your car will like you a lot better if you use premium gas.

Let me break it down in terms everyone will understand.

 

93 octane makes a bigger boom then 87 octane.

 

Legacy's have a turbo and a trubo requires a bigger bang.

 

If you put 87 octane in.... that bigger bang is not achieved. this causes the engine to operate incorrectly and possible go boom

Shall I break it down in terms that underdog will understand?

It's not about the size of the boom, it's about how quickly the boom propagates. 93 burns slower than 87.