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Question - 6G Celicas Forums

Topic #13611 16 posts Started by Shigexile
If you put turbo on your car, do you have to use premium gas?

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Yes

(and please dont post twice >smile.gif>

EDIT: To elaborate, the octane rating on gas is it's ability to resist detonation. A higher octane rating is better gas; and when you have higher pressure inside the engine, you need to use gas thats able to resist detonation better so you don't blow you engine up.

This post has been edited by shid: Jun 19, 2004 - 6:11 PM

well the thing is that i used a premium gas before on a N/A engine and felt it lag more then normal gas has.

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Have you used it on your GT?

It's better.
your never supposed to use different gas then what it calls for. it calls for 87, and you use premium gas its bad for your car.
Uhh, the GT engine does not call for 87. It calls for 91, it says so in my manual.
is that the "silver" gas (the same as "plus" gas)?

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-ssnake86+Jun 21, 2004 - 12:59 PM
-Doge+Jun 21, 2004 - 8:58 PM
-shid+Jun 21, 2004 - 2:17 PM
I don't know about old VWs or any car maker specifically.. I just picked an older car. Maybe they can!
OMG let this gas thing die already!!

Ok here is the deal, octane rating does not mean your gas burns any better/cleaner than a lower octane fuel. It means it can resist more pressure before exploding.

You use a higher octaine fuel in an engine with higher compression. Thus your car does not detonate early and you disintigrate your pistons over time. No using 93 octane in a car that needs to use 87 will not harm it but it may over time. Basically what it does is throw your timing off ever so slightly, basically retarding it. Here is a true example, my idiot friend had a gsxr 750 and he decided that he would put 110 octane fuel in it. About a day of riding later he heard this knocking noise in it. Took it to the shop and they said he bent a rod and due to the high octane gas.

Now if you have a car that is turbo, thus higher compression and you put 87 octane in it, your car is going to detonate early. This is going to put a big strain on your pistons and it is going to eat away the tops of them, and basically your pistons will disintigrate.

I wish I had some pics of piston detonation to show you guys, but I can't find them. I used to have some pics of detonation on a 2-stroke jet ski motor, and also on one of my friends motocross bike.
I didn't know the 5sfe required 91 octane, I always thought since it was a economy engine 87 octane was the standard for it, heh learn somethin' new everyday.
the GT calls for 91? really i would of never guessed. i also thought since it is supposed to be an economy car it would require 87. i've been putting 87 in it ever since i owned it, which has only been about 4 months. i hope i havnt screwed my car up... >confused.gif>
snake, I was putting 87 in it for 8 months; and then I switched to 91; the car feels soooo much better
i would put in 91, if the 87 wasnt $2.20 a gallon here in San Diego. i think 91 around 2.50