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octane?? - 6G Celicas Forums

Topic #31567 10 posts Started by 1994toyotaracer
i was wondering what king of increases i would see if i used 93 octane in my celica
deja vu, i think i read a thread like this not too long ago...as for your question, absolutely nada. your NA 5s isnt going to have issues with detonation with recommended 87 octane, higher octane isnt more "powerful" or anything, it just resists detonation better.

This post has been edited by celicaST: Dec 8, 2005 - 9:31 PM

I think Bigfoot is blurry, that's the problem. It's not the photographer's fault. Bigfoot is blurry. And that's extra scary to me, because there's a large, out-of-focus monster roaming the countryside.
Depends on ur engine. An ST engine will see no difference. But putting 93 octane in a GT will make a slight difference. It does resist detonation better and may give a tiny jump in performance. When i started filling up with premium in my GT, it made a significant increase in fuel economy. Read the manual. Putting in 93 octane (w/ a GT) won't hurt anything...'cept ur wallet.
87 93?!?!!?

jesus our standard here is 95 with premium been 101 octane in the uk

and i thought we where worse off ;(

lol
We have a different way of measuring octane over here.

The UK uses RON, or Reasearch Octane Number.
MON, or Motor Octane Number, is another way to measure octane ratings.
The US uses the average of the two.
87 works OK in a GT, 91 or higher is preferred. It actually says to use 91 or higher for best performance in the owners manual. The computer will retard your timing to keep the 87 from pinging. The ST motor didnt have the compression to make any use of a higher octane.
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QUOTE(97GTinKC @ Dec 28, 2005 - 1:20 PM) [snapback]372044[/snapback]
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87 works OK in a GT, 91 or higher is preferred. It actually says to use 91 or higher for best performance in the owners manual. The computer will retard your timing to keep the 87 from pinging. The ST motor didnt have the compression to make any use of a higher octane.



does it really say to use hign octane 91 gas on your 5sfe in the owers mannual. my celica didnt come with a owners mannual so i wouldnt know
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QUOTE(Alchemist_57 @ Dec 25, 2005 - 7:59 PM) [snapback]371027[/snapback]
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Depends on ur engine. An ST engine will see no difference. But putting 93 octane in a GT will make a slight difference. It does resist detonation better and may give a tiny jump in performance. When i started filling up with premium in my GT, it made a significant increase in fuel economy. Read the manual. Putting in 93 octane (w/ a GT) won't hurt anything...'cept ur wallet.


Agreed - a very slight difference. Another thing I noticed is a smoother idle. Some people will argue with me on this point but I se it everytime I put lower grade gas in - Idle gets rougher. It may just be that the ECU is used to the better gas or what someone above said about the timing not being retarded enough IDK.
I always use 98 RON in my celica.
The manual said to use premium unleaded,
and premium unleaded over here is 98.

98 ST204 ZR - Black Beauty - Roaming the streets of Sydney73 TA22 LT - Tiffany Blue - Mint Classic Weekend Cruiser75 TA22 LT - Snow White - Mint Classic Weekend Cruiser77 RA28 LT - Flubber Green - Mint Classic Weekend Cruiser94 MX-5 NA8 Clubman - Red Racer - Looking for cornersWIP Project: 69 RT40 Corona, 2nd WIP Project: 66 RT40 1600s Corona86 Corona RT142 - Daily Driver6GC 4 Life Baby!!!
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QUOTE(tovejas @ Jan 13, 2006 - 11:23 AM) [snapback]378082[/snapback]
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QUOTE(97GTinKC @ Dec 28, 2005 - 1:20 PM) [snapback]372044[/snapback]
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87 works OK in a GT, 91 or higher is preferred. It actually says to use 91 or higher for best performance in the owners manual. The computer will retard your timing to keep the 87 from pinging. The ST motor didnt have the compression to make any use of a higher octane.



does it really say to use hign octane 91 gas on your 5sfe in the owers mannual. my celica didnt come with a owners mannual so i wouldnt know



Yes, for the North American GT 5SFE only, not the ST, something like: "while you can use 87 octane regular fuel, for best performance, use premium 91 or higher octane fuel" (that may not be an exact quote)

I also seem to get better mileage and performance with premium. heck, its only a couple of dollars per tank difference, and seems to pay for itself...