Using Premium Fuel in WRX's
Registered User
Joined: Apr 2003
Posts: 1,013
From: california, LOS ANGELES
Car Info: dream car Subaru STi
anything not 91 or higher is gona mess up ur engine bad. they sell 91 and 100 octane at the pumps at the 76 gas stations, not all. only some 76 stations. use high octane! this is a high performance car!
Registered User
Joined: Feb 2003
Posts: 414
From: Nether reach of CA delta
Car Info: 03 WRX Sedan MBP/17X7.5 SSR Comps/225 Kumho MX
Buying the minimal 91 octane gas for your WRX is like buying insurance against ignition knock. Pre-igition (engine knocking or pinging) can destroy a turbo engine. It was the same deal with my '90 Eclipse GS Turbo.
In a perfect world, your engine is perfectly tuned and all components are running exactly right in all conditions. That's when you can use a lower octane gas, because a perfectly tuned turbo engine will not knock on the lower octane gas.
In the real world... out on the highways, a lot of turbo engines are not perfectly tuned for all driving conditions all of the time. Buying a higher octane gas will give your engine more margin for error and less opportunity to knock.
Follow your maintenance schedule, keep the engine running good and use the 91 octane gas. I got 260K miles off of my Eclipse turbo engine, and I am looking to better that with the WRX!
In a perfect world, your engine is perfectly tuned and all components are running exactly right in all conditions. That's when you can use a lower octane gas, because a perfectly tuned turbo engine will not knock on the lower octane gas.
In the real world... out on the highways, a lot of turbo engines are not perfectly tuned for all driving conditions all of the time. Buying a higher octane gas will give your engine more margin for error and less opportunity to knock.
Follow your maintenance schedule, keep the engine running good and use the 91 octane gas. I got 260K miles off of my Eclipse turbo engine, and I am looking to better that with the WRX!
Registered User
iTrader: (1)
Joined: Mar 2003
Posts: 660
From: PA
Car Info: TXS tbe, perrin goodies, v7 sti struts...bla bla bla lots of stuff!
I've not put anything lower than 93 octane since I got it... I don't think the dealer put that in it... I made sure it was almost empty then filled it with 93. $1.40 for the premium stuff....hmmmm I'm paying close to $1.90 or so per gallon... yuck
-Nigel
-Nigel
Registered User
Joined: Nov 2003
Posts: 48
From: Saratoga
Car Info: 2004 WR Blue WRX
I use premium all the time now, but for a while I used 89 and it ran fine. No noise or anything, power is reduced with it and doesnt feel as smooth, but doable for a while. Why don't you trade off 91 and 89, just a thought
Re: Using Premium Fuel in WRX's
Originally posted by Bob DiRado
I just bought an 03 wrx sedan about just under a week ago and the delivery specialist said that i really should use 91 octane. now where i live, thats some expensive fuel, i figured that i would use it at least until the break in period was over, but has anyone been runing there's on 87? any problems
I just bought an 03 wrx sedan about just under a week ago and the delivery specialist said that i really should use 91 octane. now where i live, thats some expensive fuel, i figured that i would use it at least until the break in period was over, but has anyone been runing there's on 87? any problems
exactly how much of a difference is 87 and 91? for us in california bay area, its only like 20 cents per gallon difference.
Guest
Posts: n/a
Youir ECU will change to a "Bad Gas" map if you use lower than 91 octane.
Anyone that did the slightest amount of research before they bought their WRX should have known that 91+ was a must and also should have known that the wrong side of 25mpg in mixed driving was to be expected.
Anyone that did the slightest amount of research before they bought their WRX should have known that 91+ was a must and also should have known that the wrong side of 25mpg in mixed driving was to be expected.
Registered User
Joined: Nov 2002
Posts: 261
From: So. Ca., CA USA
Car Info: 03 WRX / 08 Forester
Originally posted by FUNKED1
The ECU will adjust to lower octane than 91. Unless you are modded it is not a big deal. You will just have less power.
The ECU will adjust to lower octane than 91. Unless you are modded it is not a big deal. You will just have less power.
- Kean
Guest
Posts: n/a
Originally posted by Kean
The manual clearly states that you shouldn't run anything lower than 91 octane (other than situations when it's necessary).
The manual clearly states that you shouldn't run anything lower than 91 octane (other than situations when it's necessary).
If you wanted to use low octane gas you should have bought an RS, same car, different engine, no turbo.
Registered User
Joined: Nov 2002
Posts: 1,687
From: Land 'O' the Ports, Orygun
Car Info: Broken ass stock '02 WRX
I was at a pump in oregon when the kid accidentally put 87 in... my car ran SLOW as hell and jerked sometimes.... DONT do it dude... i got back home and drained the rest of the fuel and gave it to my dad...
