switching octane?
19-Dec-2003, 06:35 PM
#1
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switching octane?
say i use the minimum octane i can get... regular at chevron is 87 i think.......will it harm my car if i put in plus or supreme in every once in a while for ***** and giggles? it will increase hp rite?
19-Dec-2003, 06:39 PM
#3
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coo cuz i put in the medium octane this mornin and it dawned on me that it mite be bad... but im glad its ok.... ya about the no power gain.... it dont feel too different, just on my wallet
19-Dec-2003, 06:42 PM
#4
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dont waste your money, unless you are pushing over 10 compression (just a guess, not sure what the recomended is) than its a big waste of money, your sig says you have an ex, so it wont give you any performance gains or anything, your factory manual specifies 87 so might as well use it... the only reason one needs to use high octane is to prevent pre ignition/ detonation and knnocking ect associated with high compression engines/ turbo/ nitrous... so unless your running any of that, save your money...
on the other side, it wont hurt anything in your engine, you can use it anytime you want... its just a waste of money is all im getting at...
on the other side, it wont hurt anything in your engine, you can use it anytime you want... its just a waste of money is all im getting at...
20-Dec-2003, 08:55 AM
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Or you could advance your timing to take advantage of the increased octane. The fuel recommended is also related to the timing. I have mine at full advance using 93 octane, it is alot more responsive in the low end.
21-Dec-2003, 10:54 AM
#11
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Originally posted by bigdaddygofast
Or you could advance your timing to take advantage of the increased octane. The fuel recommended is also related to the timing. I have mine at full advance using 93 octane, it is alot more responsive in the low end.
Or you could advance your timing to take advantage of the increased octane. The fuel recommended is also related to the timing. I have mine at full advance using 93 octane, it is alot more responsive in the low end.
21-Dec-2003, 01:57 PM
#14
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By initiating the combustion event sooner (advanced timing) the cylinder pressure/temp. increases due to the flame kernel expanding while the cylinder is still compressing the a/f mixture. So, when combustion occurs there is there is more energy available. That is the reason the timing is set for 87 octane gas. If you advance too far on 87 octane the cylinder pressure/temp will increase beyond the octane rating of the fuel and thats when you develop the knock-knock ping-ping. The a/f mixture has just exploded uncontrolled and with increased force before the connecting rod had gone beyond TDC (usually 12-16 degrees past TDC). The octane rating is just the resistance to detonation in a given environment.
22-Dec-2003, 11:00 AM
#19
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Originally posted by bbarbulo
does pumping the neighbor's wife have any ill effects??
does pumping the neighbor's wife have any ill effects??
22-Dec-2003, 11:31 AM
#20
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octane... the higher the number the more stable it is. the more stable it is the more compression and spark is needed to make it go boom. if you keep stock compression and spark then higher octane will take longer to burn.... longer to burn means not reaching maxium pressure in the combustion chamber at the right point....
