110 octane

[mmatl16]

I was thinking about going to the track on some 110 octane but since I dont have a boost controller or any kind of fuel management it isnt going to help is it......

[Joe]

Octane is a measure of how hard a fuel is to combust and resist pre-ignition/detonation. the higher the number the harder it is to burn. running a higher octane than needed (race gas for example) will only kill your performance.

you need to run the lowest octane you can without pinging. on a stock RB, pump gas (91+) is fine.

ive put race gas in my car once, when it was 95 degree air temprature and i was doing a grip event. it was 1.5 hours on track, HOT. BAD. even then i just put 4 gallons in and the rest 91. just enough to bump it a few points. no detonation, no pinging, no problems.

[biglipzit]

Is it true that they commercially add toulene or xylene to raise the octane in gasoline? I do know that they make up the main part in octane boosters.. Found this online would you trust it? In the caribbean we only get one grade of gasoline which can range from 92-94 octane.

FORMULA 1TouleneR+M/2...114Cost...$2.50/galMixtures with 92 Octane Premium10%...94.2 Octane20%...96.4 Octane30%...98.6 OctaneNotes: Common ingredient in Octane Boosters in a can. 12-16 ounces will only raise octane 2-3 *points*, I.e. from 92 to 92.3. Often costs $3-5 for 12-16 ounces, when it can be purchased for less than $3/gal at chemical supply houses or paint stores. FORMULA 2XyleneR+M/2...117Cost...$2.75/galMixtures with 92 Octane Premium10%...94.5 Octane20%...97.0 Octane30%...99.5 OctaneNotes: Similar to Toulene. 12-16 ounces will only raise octane 2-3 *points*, I.e. from 92 to 92.3. Usually mixed with Toulene and advertised as *race formula*.

FORMULA 3Methyl-tertiary-butyl-ether (MTBE)R+M/2...118Cost...$3.50/galMixtures with 92 Octane Premium10%...94.6 Octane20%...97.2 Octane30%...99.8 OctaneNotes: Oxygenate. Very common in octane booster products. Has lower BTU content than toulene or xylene, but oxygenate effect makes the gasoline burn better and produce more energy.

FORMULA 4Methanol or EthanolR+M/2...101Cost...$0.60 - $1.75/galMixtures with 92 Octane Premium10%...94.3 Octane (Methanol)10%...94.7 Octane (Ethanol)20%...Not RecommendedNotes: Methanol is wood alcohol. Ethanol is grain alcohol and found in Gasohol in 10% ratios. Both alcohols are mildly corrosive and will eat gas tank linings, rubber and aluminum if used in excessive ratios. Main ingredient in "Gas Dryers", combines with water.

FORMULA 5Isopropyl Alcohol and Tertiary Butyl AlcoholR+M/2...101Cost...$0.60-$1.50/galMixtures with 92 Octane Premium10%...94.5 Octane20%...Not Recommended30%...Not RecommendedNotes: Similar to Methanol/Ethanol. Isopropyl Alcohol is simply rubbing alcohol.

[goofynick6]

Until you're pushing 18psi and advancing timing or running hard in hot weather, I wouldn't worry about using it.

Nick

[mmatl16]

what about just mixing in some 100 with my 91....will that make it run a little better

[Joe]

what about just mixing in some 100 with my 91....will that make it run a little better

your missing the pointif you arent detonating your car will run worse on higher octane

octane does NOT equal horsepower.

[goofynick6]

Mixing some 100 with 91 to make 93 will be ok, but probably not worth it unless you mod the engine some. Like Joe said, unless you are detonating don't worry about it. The higher octane will reduce the chance of the gas being lit by something other than the sparkplug, as in a hot spot on the piston skirt, a valve or hot edge in the combustion chamber. So, until you get to the point where things are getting hotter than normal in that combustion chamber, from something like a turbo cranking high boost or really advanced timing, then you're fine on what you have.

Nick

[biglipzit]

lol i was running 18 psi and detonating you remember?

[Joe]

Mixing some 100 with 91 to make 93 will be ok, but probably not worth it unless you mod the engine some. Like Joe said, unless you are detonating don't worry about it. The higher octane will reduce the chance of the gas being lit by something other than the sparkplug, as in a hot spot on the piston skirt, a valve or hot edge in the combustion chamber. So, until you get to the point where things are getting hotter than normal in that combustion chamber, from something like a turbo cranking high boost or really advanced timing, then you're fine on what you have.

Nick

tee hee

if your piston skirt is pre-igniting your AF mix something is seriously wrong

[Wulfgang]

Lol, maybe his piston has its skirt over its head for servicing...

j/k Nick. We know what you meant.

[goofynick6]

LOL...was typing too quickly...I guess I meant ringland/topland area. Basically the edge/side of the piston