Which Octane are you running? School me.

Started by Gunz, January 08, 2009, 11:37:24 PM

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preddy08

The higher the octane the harder it is to make it cumbust.
Just a little 81hp trail bike.


Flynbyu

#16
High-performance engines typically have higher compression ratios and are more prone to detonation, so they require higher octane fuel. A lower-performance engine will not generally perform better with high-octane fuel, since the compression ratio is fixed by the engine design. You're wasting money running 91 or higher octane in your 4 - 6 cylinder car or truck. I would not run anything higher than 87 in an ATV unless it was highly modified or was a high compression set up.

Higher-octane fuel isn't harder to ignite in the usual way, the octane rating just indicates how easily the fuel can SPONTANEOUSLY ignite before the flame-front reaches it. "Spontaneous pre-ignition" is just another phrase for "detonation" or "knock"; higher-octane fuels resist knocking better than low-octane fuels because they are a more resistant to the flame front, making ignition a little harder.


~Brian




2003 Yamaha Raptor





Yamaha Raptor Forum

BLU700R

Awesome! Where would i even find such smelly good fuel? lol i realize that with my mods i could run pump gas but everyone says it smells good and well i need proof! LOL
+2 TB+GYTR full exhaust+12.1 JE+PCIII+15T+HotCams2+GYTR Intake+Iridium Plug=Crazy Badassness


Man do I miss my wheeler :(

Peelz

Quote from: preddy08 on January 12, 2009, 09:41:53 AM
The higher the octane the harder it is to make it cumbust.

"cumbust" wtf is that? Is that when the condom pops from sheer semen volume? ;) :lol:

-Grammar Ninja out.
Krandall: "peelz. I'll be real with you. As much as I hate on you for soccer, I really don't mind it"


Flynbyu

Quote from: Peels660 on January 12, 2009, 01:44:29 PM
Quote from: preddy08 on January 12, 2009, 09:41:53 AM
The higher the octane the harder it is to make it cumbust.

"cumbust" wtf is that? Is that when the condom pops from sheer semen volume? ;) :lol:

-Grammar Ninja out.

Preddy must be on some shit today.

That or he's been watching porn.

:lol:

~Brian
2003 Yamaha Raptor





Yamaha Raptor Forum

Peelz

Quote from: Flynbyu on January 12, 2009, 03:12:10 PM
Quote from: Peels660 on January 12, 2009, 01:44:29 PM
Quote from: preddy08 on January 12, 2009, 09:41:53 AM
The higher the octane the harder it is to make it cumbust.

"cumbust" wtf is that? Is that when the condom pops from sheer semen volume? ;) :lol:

-Grammar Ninja out.

Preddy must be on some shit today.

That or he's been watching porn.

:lol:

~Brian

Yep, it is his subconscious talking. :lol:
Krandall: "peelz. I'll be real with you. As much as I hate on you for soccer, I really don't mind it"


Kamakazi

ive always used the rule of thumb, 10:1 compression to 12:1 requires 91 octane, and ive never had to make a rule for any higher ???
98% of north americans that hit the ditch say "oh shit", the other 2% are from saskatchewan and say "hold my beer and watch this"



1badazz_700r

If you want a good smell cheaper. go to the airport and by avgas and mix it with regular gas. I wouldnt run it straight likei used to,cause i read it does not lubricate its really dry. I have ran it straight in my drag car and my raptor with no issues what so ever. just know what i read. But it does smell pretty good :thumbs:

Just a little 778
105.5 WK cylinder CP 11:1
hotrods +5 crank
racersedge +2 head,with webb4
54mmTB with custom intake
sparks X-6exhaust
PC5/w autotune
dynatek programmable
slingshot lockup
+3 stock swingarm
hiper dual beadlocks/w gncc holeshots
flexx bars,burgard+2stem/w antivibe
ASV's
odi's

Peelz

Avgas...I get that from my buddy pretty cheap. Good stuff. 110?
Krandall: "peelz. I'll be real with you. As much as I hate on you for soccer, I really don't mind it"


1badazz_700r


Just a little 778
105.5 WK cylinder CP 11:1
hotrods +5 crank
racersedge +2 head,with webb4
54mmTB with custom intake
sparks X-6exhaust
PC5/w autotune
dynatek programmable
slingshot lockup
+3 stock swingarm
hiper dual beadlocks/w gncc holeshots
flexx bars,burgard+2stem/w antivibe
ASV's
odi's

Flynbyu

#25
Quote from: 1badazz_700r on January 12, 2009, 06:12:36 PM
If you want a good smell cheaper. go to the airport and by avgas and mix it with regular gas. I wouldnt run it straight likei used to,cause i read it does not lubricate its really dry. I have ran it straight in my drag car and my raptor with no issues what so ever. just know what i read. But it does smell pretty good :thumbs:

Correct. Avgas does not lubricate like jet based fuels. Jet fuels (Jet A, Jp-1, Jp-4, Jp-7, Jp-8 etc.) are kerosene based fuels. Turbine and jet engines operate at higher rpms and higher alititudes and they require a fuel that has a higher freezing point that gasoline based fuels. The kerosene base is used for it's lubricating properties, ability to dissipate static electricity, and due to it's higher freezing point freezing point (-40 to -47C).

Avgas has a lower and more uniform vapor pressure than automotive gasoline. It keeps it in the liquid state at high-altitude, preventing vapor lock. 100LL contains tetra-ethyl lead (TEL), a lead based anti-knock compound, but less than the "highly-leaded" 100/130 aviation fuel it replaced back in the 1980's. Avgas contains 2 grams of lead per US gallon.

I would not recommend using it in your ATV or automobile without blending it.

~Brian
2003 Yamaha Raptor





Yamaha Raptor Forum

Peelz

Great write up Brian. :thumbs:  Mix it....My buddy with the Banshee swears by it. Works on jets... Mixes 50/50 with 91 before mixing the oil. Has a killer aroma at full throttle! :lol:
Krandall: "peelz. I'll be real with you. As much as I hate on you for soccer, I really don't mind it"


Flynbyu

Quote from: Peels660 on January 13, 2009, 08:37:10 AM
Great write up Brian. :thumbs:  Mix it....My buddy with the Banshee swears by it. Works on jets... Mixes 50/50 with 91 before mixing the oil. Has a killer aroma at full throttle! :lol:

Stuff they drill into you during ground school.

~Brian
2003 Yamaha Raptor





Yamaha Raptor Forum

Colorado700R

Quote from: Flynbyu on January 13, 2009, 08:34:09 AM
Quote from: 1badazz_700r on January 12, 2009, 06:12:36 PM
If you want a good smell cheaper. go to the airport and by avgas and mix it with regular gas. I wouldnt run it straight likei used to,cause i read it does not lubricate its really dry. I have ran it straight in my drag car and my raptor with no issues what so ever. just know what i read. But it does smell pretty good :thumbs:

Correct. Avgas does not lubricate like jet based fuels. Jet fuels (Jet A, Jp-1, Jp-4, Jp-7, Jp-8 etc.) are kerosene based fuels. Turbine and jet engines operate at higher rpms and higher alititudes and they require a fuel that has a higher freezing point that gasoline based fuels. The kerosene base is used for it's lubricating properties, ability to dissipate static electricity, and due to it's higher freezing point freezing point (-40 to -47C).

Avgas has a lower and more uniform vapor pressure than automotive gasoline. It keeps it in the liquid state at high-altitude, preventing vapor lock. 100LL contains tetra-ethyl lead (TEL), a lead based anti-knock compound, but less than the "highly-leaded" 100/130 aviation fuel it replaced back in the 1980's. Avgas contains 2 grams of lead per US gallon.

I would not recommend using it in your ATV or automobile without blending it.

~Brian

Also the avgas works well with the turbo chargers used on aircraft.  Turbos on aircraft are not to build "extra" HP for the most part they are designed to maintain the engines HP at altitude.  Do to this methodology of employment, the cylinder pressure is more consistant across all the alttiudes becuase although the turbos push more total volume at higher altitudes, the mass of that volume is less do to less oxygen content.

Flynbyu

99% of turbocharged aircraft built today require Jet A.

~Brian
2003 Yamaha Raptor





Yamaha Raptor Forum