What Is The Main Reason That We Need 91+ Octane On Our Cars? I Know It Runs Cleaner But Friend Is
11-17-2005, 05:31 PM
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What Is The Main Reason That We Need 91+ Octane On Our Cars? I Know It Runs Cleaner But Friend Is
Asking Me Why And Is Pissing Me Off I Wanna Shut Him Up
11-17-2005, 05:42 PM
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IIRC, because of the added pressure and heat in our combustion chambers from being turbocharged the
extra octane prevent "pinging" or pre-detonation of fuel. Someone else can probably explain it better.
11-17-2005, 05:50 PM
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Re: What Is The Main Reason That We Need 91+ Octane On Our Cars? I Know It Runs Cleaner But
Octane is simply a fuels resistance to burn. Because of the increased compression(boost) and increased temps a higher octane rating is needed. The lower octane fuels will combust prematurley (from temp or compression) causing bad things to follow. Hope this is simple enough and helpful.
11-17-2005, 08:15 PM
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THe way I understand it...
<center><img src="http://www.antonine-education.co.uk/Physics_A2/Options/Module_7/Topic_4/Otto.jpg"></center><p>The more octane, the more compression the fuel can take before it combusts. If theres less octane the fuel will prematurely combust. This sounds harmless but you have to think how a combustion engine works. Combustion pushes the piston down which turns the drive shaft which turns the wheels and the theigh bone is connected to the knee bone and the knee bone... I'm getting off topic. Anyways, the piston moves up and down in the cylinder. As it moves upward it creates more compression in the cylinder. Premature ejaculation, i mean combustion, means that the fuel has exploded before the piston has reached its full height at the top of the cylinder. So as the piston is still moving upward the fuel has already combusted. This can cause a lot of expensive problems in the future as well as cause the engine to run with less efficiency.
