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Tuned on 93 octane, forced to use 87 (for a short period)

7K views 7 replies 6 participants last post by  STiDriven 
#1 ·
Whats up guys/ gals, been a while since I've posted on here but just a quick question (mostly to help me sleep better at night) I live on Long Island and as most everyone knows we're experiencing an absurd fuel crisis. My 2005 WRX is pro-tuned on 93 octane fuel which I always use however in this case it is impossible to find a station that has a supply of 93. I filled up with 87 this morning (I had a quarter a tank of 93 in my car already) and thought I might try to find some octane booster. That searched has proved difficult as well. Im just curious to know if this will be detrimental to my car at all. I baby the car (even more so during this fuel crisis to conserve gas) and I just want to know if mixing the 87 with the 93 will be at all detrimental to the car. Should be able to get premium fuel again next time I get gas, so I'll fill up again at about a half a tank to sort of balance it out. Just need words of assurance, I feel as though im being neglectful when I really had no other alternative. Thanks in advance to anyone willing to answer.

-Rob
 
#2 ·
You would have to buy so much octane booster to bring it up to 93 it would be absurd.

Drive the car very conservatively, stay totally out of boost, you should be ok. There were 1 or 2 other people recently posting who had the same issue as you, it was unavoidable.
 
#3 ·
Thanks man....yea staying out of boost hasnt been an issue at all (gotta conserve) Hopin sometime over the weekend Premuim will be available again and I can top it off again with that. Thanks again
 
#4 ·
Octane booster raises the effective octane rating something like .1, so it's not really effective.

The car has knock control strategies to deal with lower-quality gas. Your car will likely not run optimally, and may be pulling timing a bit. As long as you're not beating on the car and your cruise/part-throttle timing isn't too aggressive, you should be fine.
 
#6 ·
yea hopefully this crisis BS eases up within the next week or so....I can at least fill up with more premium so I can use it all up evenly. Thanks for the reassurance
 
#7 ·
Keep race gas on hand for emergencies ;)
 
#8 ·
I'd be careful. This summer driving to Lincoln, I was in-between Kansas City and Nebraska City out of gas. All I could find was 89oct. and I am also tuned for 93. I plugged in my accessport to monitor for knock as I continued, I figured if I stayed off boost I'd be fine. To my surprise, it was REALLY EASY to get knock even at partial throttle at lower RPMs. Think cruising in 6th, you get behind someone and slow to 60mph; you get back on the gas a little (1/4 to 2/5's throttle) to get back up to speed - feedback knock of 2 - 5 on occasion. I was ok cruising but that never happened on 93.

You just need to really baby it accelerating, more so than 'just stay out of boost'



Or - if REALLY in a bind; go to Lowe's or Home Depot and pick up a gallon of Toluene (111 Octane) or Xylene (117 octane). You can use that as an octane booster mixed with crappy gas. I wouldn't do it all the time, but I've done it before at a track event out of town in the middle of nowhere that only had 91 octane and it did work. That is what all the old DSM guys used.

But if you have access to racegas - it is a whole lot cheaper than a gallon of Toluene or Xylene.
 
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