Does 93 octane run hotter than 91

AltecBX · 02-18-2013, 10:53 AM

Does 93 octane run hotter than 91? Or does it run hotter because it could be run leaner?

enrita · 02-18-2013, 11:13 AM

octane does not matter. probably leaner

Jeff@TopGearSolutions · 02-18-2013, 11:58 AM

No to answer your question directly.

Higher octane is actually harder to burn. That's why you usually need more ignition advance then its 87 or 89 or 91 octane counterparts.

Since higher octane is harder to burn that is also why it makes it less susceptible to knock.

Which is also why putting say 93 octane in a car that needs 87 octane won't do anything and might actually diminish performance if not tuned.

AltecBX · 02-18-2013, 11:23 PM

Thanks guys. Good to know.

fazi13 · 02-19-2013, 01:09 AM

Also remember seeing a bit on 5th gear showing what different octanes do on different cars and basically, its best to run what's recommended. (although 5th gear is European and Euro RON's are usually around 91+ octane) basically, unless you have a 93 octane tune 91 is best. But I do believe 93 is better than 89 if you're in an area with 87, 89, 93.

02-18-2013, 10:53 AM	#1
AltecBX Colonel 324 Rep 2,663 Posts Drives: BMW 335xi Sedan; BMW M3 ZCP Join Date: Nov 2007 Location: NYC iTrader: (0) Garage List 2018 BMW M3 ZCP [0.00] 2007 BMW 335Xi [0.00]	Does 93 octane run hotter than 91 Does 93 octane run hotter than 91? Or does it run hotter because it could be run leaner?
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02-18-2013, 11:13 AM	#2
enrita Major General 161 Rep 7,377 Posts Drives: 335i - Big turbos Join Date: Sep 2008 Location: Italian in Sweden iTrader: (0)	octane does not matter. probably leaner __________________ 07 335i AT - MOTIV 750 - MHD E85 BMS flash - BMS PI - JB4G5 - Okada Coils - NGK 5992 Plugs - Helix IC - Snow Stg. 3 - Stett CP - Custom midpipes with 100 HJS Cats - Bastuck Quad - PSS10 - QUAIFE LSD - BMS OCC - Forge DVs - AR OC - ALCON BBK - M3 Chassi - Dinan CP - Velocity M rear Toe arms - Advan RZ-DF - LUX H8 - Level 10 AT upgrade
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02-18-2013, 11:58 AM	#3
Jeff@TopGearSolutions 3441 Rep 79,211 Posts Drives: C6 Z06, 09 335i, 10 335xi Join Date: Dec 2008 Location: www.TopGearSolutions.com iTrader: (37)	No to answer your question directly. Higher octane is actually harder to burn. That's why you usually need more ignition advance then its 87 or 89 or 91 octane counterparts. Since higher octane is harder to burn that is also why it makes it less susceptible to knock. Which is also why putting say 93 octane in a car that needs 87 octane won't do anything and might actually diminish performance if not tuned.
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02-18-2013, 11:23 PM	#4
AltecBX Colonel 324 Rep 2,663 Posts Drives: BMW 335xi Sedan; BMW M3 ZCP Join Date: Nov 2007 Location: NYC iTrader: (0) Garage List 2018 BMW M3 ZCP [0.00] 2007 BMW 335Xi [0.00]	Thanks guys. Good to know.
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02-19-2013, 01:09 AM	#5
fazi13 Private First Class 28 Rep 161 Posts Drives: 2008 335i Manual Join Date: Feb 2013 Location: SF Bay Area iTrader: (0) Garage List 2008 BMW 335i [0.00]	Also remember seeing a bit on 5th gear showing what different octanes do on different cars and basically, its best to run what's recommended. (although 5th gear is European and Euro RON's are usually around 91+ octane) basically, unless you have a 93 octane tune 91 is best. But I do believe 93 is better than 89 if you're in an area with 87, 89, 93.
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