The Subaru SVX World Network   SVX Network Forums
Live Chat!
SVX or Subaru Links
Old Lockers
Photo Post
How-To Documents
Message Archive
SVX Shop Search
IRC users:

Go Back   The Subaru SVX World Network > SVX Main Forums > Technical Q & A

Reply
 
Thread Tools Display Modes
  #1  
Old 08-02-2004, 08:46 PM
nismo887
Guest
 
Posts: n/a
premium gas?

the svx asks for premium gas, but does it really matter? other than the added performance.
Reply With Quote
  #2  
Old 08-02-2004, 08:56 PM
Chiketkd's Avatar
Chiketkd Chiketkd is offline
Row faster...I hear banjos!!!!
 
Join Date: Mar 2004
Location: Charlottesville, VA
Posts: 10,334
Re: premium gas?

Yes, it does matter. Your engine will knock if you use any grade lower than 91 octane.

However, if you have to use a lower grade 89/87 fuel, it will do no permanent damage to your car, as our engines have knock sensors that will dial back timing when knock is detected.

-Chike
Quote:
Originally posted by nismo887
the svx asks for premium gas, but does it really matter? other than the added performance.
__________________
"Wise men talk because they have something to say; fools, because they have to say something." - Plato

2013 Cosmic Blue 5spd Evo X GSR
2006 Galaxy Gray 6MT RX-8 (sold)
2006 Steel Gray WRX TR (sold)
1996 Brilliant Red SVX L (sold)
Reply With Quote
  #3  
Old 08-02-2004, 10:03 PM
Green1995SVX
Guest
 
Posts: n/a
Re: premium gas?

Quote:
Originally posted by nismo887
the svx asks for premium gas, but does it really matter? other than the added performance.
Yes, Nismo, it does matter. Just like Chike said, your engine will knock if you use any grade lower than 91. If 92-93 is available in your area, that would be an even better bet! Also, would you mind editing your location to indicate something more specific? The "U.S." is a pretty large area!

Thanks, and enjoy yourself here.

Mike
Reply With Quote
  #4  
Old 08-03-2004, 02:17 AM
UberRoo's Avatar
UberRoo UberRoo is offline
SVX Appeal
 
Join Date: Feb 2004
Location: Puget Sound, Washington
Posts: 843
There is no consensus on this issue. I believe that it will simply lower performance as long as the knock sensors detect pinking. Others believe that the ECU will permanently recalibrate itself and original performance will never be fully restored. I've seen no evidence of the latter, and it seems illogical and improbable to me, but I digress [lest I stir up an old debate.]

We do all tend to agree that no damage will occur unless your knock sensors are defective. (Check the codes to find out.) Some vehicles will exhibit unpredictable symptoms, such as hesitation; low, high or unsteady idle speed; poor mileage; surging; and even stalling. These things rarely happen and should not normally affect a good engine.
__________________
1994 LSi, Laguna Blue SVX Appeal
1992 LS-L, Ebony Pearl SVX-Rated
UberLocker
Reply With Quote
  #5  
Old 08-03-2004, 09:49 AM
Chiketkd's Avatar
Chiketkd Chiketkd is offline
Row faster...I hear banjos!!!!
 
Join Date: Mar 2004
Location: Charlottesville, VA
Posts: 10,334
I agree with you UberRoo. I seriously doubt anything long-term will be saved on the ECU and if something is, the ecu will re-learn itself once premium gas is used again.

Nismo, if you want to get the best gas mileage or even the ultimate performance out of your SVX, you need to use premium. If not, then running regular gas shouldn't hurt your car - as long as your knock sensors are working.

-Chike
Quote:
Originally posted by UberRoo
Others believe that the ECU will permanently recalibrate itself and original performance will never be fully restored. I've seen no evidence of the latter, and it seems illogical and improbable to me
__________________
"Wise men talk because they have something to say; fools, because they have to say something." - Plato

2013 Cosmic Blue 5spd Evo X GSR
2006 Galaxy Gray 6MT RX-8 (sold)
2006 Steel Gray WRX TR (sold)
1996 Brilliant Red SVX L (sold)
Reply With Quote
  #6  
Old 08-03-2004, 09:54 AM
IggDawg's Avatar
IggDawg IggDawg is offline
0h n0es!
 
Join Date: May 2002
Location: Marlboro, MA
Posts: 267
Send a message via ICQ to IggDawg Send a message via AIM to IggDawg
given the tendancy to fail of the early 90's vintage knock sensors, I wouldn't do less than premium except in the case of emergency. but seriously, spring the extra 20 cents for premium. if you're putting in 10 gallons, that's the price of 8 gumballs. 8 gumballs vs the health of your engine. you decide.
__________________
IggDawg is cool

-IggDawg

1992 Teal SVX LS-L 160k miles
4.11:1 final drive, K&B dropsprings, ART front rotors, stainless steel brake, aluminum underdrive crank pulley, Kuhmo Ecsta Supra 712's, K&N drop-in filter. Previously owned by Alacrity024. FOR SALE

1994 SVX LSi, Barcelona Red #1659, build date 11/93, 117k miles, RIP
ECUtune stage 1, bead crush, smallcar shift kit, TB bypass, SS brake lines, silencer removed, alternator and grounding wires, Mobil1 @ 117k
Reply With Quote
  #7  
Old 08-03-2004, 09:59 AM
Green1995SVX
Guest
 
Posts: n/a
mmm gumballs
Reply With Quote
  #8  
Old 08-03-2004, 10:06 AM
red95svx
Guest
 
Posts: n/a
We had an SVX in a few months ago with the check engine light on, poor idle, poor acceleration, poor gas mileage. Pulled codes for both knock sensors, which tested good. Traced the problem to the 87 octane the owner had been using for the past month or so. A few weeks later, after 2-3 tanks of 91 octane, he called to say the check enigne light went off and his performance and gas mileage was back to normal.



Don't be cheap. Gas in the U.S. is some of the cheapset gas on Earth.




Dave.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -6. The time now is 12:24 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
© 2001-2015 SVX World Network
(208)-906-1122