effect of mixing gas

**A121** · November 23rd, 2003 08:53 AM

dati velocity nilalagay ko dun sa old skul galant. ok ang hatak nya pero mas "parang mainit" ang takbo...

**Karding** · November 23rd, 2003 10:28 AM

Originally posted by yebo
karding,

sa US kaya walang benefit ang high octane kasi ang compression ratio ng engines dyan ay lower than compression ratios ng engines sa pinas. strict kasi ang emission controls dyan kaya pag tinaasan ang compression ratio, tataas din ang NOx levels kaya di pwede. so since mababa lang compression ration, di nyo need ang high octane gasoline. 87 ska 92 ron lang pwede na.

dito kasi sa pinas, 10+:1 na compression ratio ng ibang car engines kaya unleaded dito 92 ska 95 ron. tapos mga newer model cars talaga nakalagay sa owner's manual, 94 ron or better ang recommended fuel kaya forced-to-good kami sa premium.

sa East coast meron pang mga 94octane, dito sa west coast 91 na lang pinakamataas. Pero ang 91RON is only equivalent to 87octane. I read somewhere:

Most of the world uses RON (research octane number) for their octane rating. The US uses (RON+MON)/2 (MON = motor octane number) for octane rating (AKI.) The key item missing from the US ratings is the sensitivity = RON-MON. Sensitivity is around 10 typicaly.

To shorten the story US 91 octane rating assuming sensitivity of 10 should be close to RON 95-96

96RON nyo pala sa Pinas 91Octane namin sa US. Based sa readings ko, kaya mababa lang na 91 octane requirements sa high end cars dito (incl. my WRX) eh para di magastos sa gas, making the cost of ownership cheaper. Kse yung ibang Type R engine dito has a CR of 11.5:1 and still passes SMOG (emission test) just as long na may catalytic converter. Ngayon kung may ETHANOL na kahalo ang gas, malamang na mas mababa ang emissions ng auto. Kaya ko naman nabanggit na walang epek ang magkarga ng mas mataas na octane other than what the car manufacturer has recommended is because of this, to quote:

Higher octane gasoline will help my vehicle pass

One possible reason for the belief that higher-octane fuel produces lower emissions is that some brands of premium fuel contain alcohol as an octane enhancer. Ethanol has a higher octane rating than gasoline but it is the oxygen content of ethanol that affects the emissions, not the octane. The emission control system in your vehicle is designed to work effectively with the grade of fuel recommended by the manufacturer.

**woulfe27** · November 24th, 2003 07:37 PM

Originally posted by paolorenzo
My ride is a '97 Honda City A/T. I switched to Velocity, coming from Blaze. Better engine response, and lesser shift-shock. Very noticable yung naging difference, that's why I immediately emptied my last Blaze tank, and filled it up exclusively with Velocity since then... Maybe it's just psychological? :confused:

mas malayo ng 30km inaabot ng P500 ko pag naka velocity ako

**revoGSX** · November 28th, 2003 12:25 AM

ano octane rating ng caltex gold at silver?
eto pa lang kasi nasa list ko
petron: Unleaded=93; XCS=95; Blaze=96
shell: unleaded=93; premium=93; velocity=95???
caltex:silver= ???; gold=???; meron pa ba iba?

thanks

**yebo** · November 28th, 2003 11:08 AM

caltex silver 93, vortex gold 95.

sea oil (forgot their term?), 95. un regular nila 92.

**1D4LV** · November 28th, 2003 11:31 AM

i am using XCS before. medyo rough ang ride. last night nag pa full tank ako velocity. smoother sya ngayon. considering both contain the same octane ratings.

**jtdc** · November 28th, 2003 11:43 AM

Petron: Unleaded=93; XCS=95; Blaze=96
Shell: Unleaded=93; Premium=95; Velocity=95
Caltex: Silver=93; Gold=95

meron pa ba iba? yes, meron pa.

sa mga Seaoil, FlyingV, Total, CityOil, etc.

basta unleaded = 93.
pag premium gas nila (iba iba ang tawag)= 95.

**buddyclub** · December 3rd, 2003 12:38 PM

hmm..mkka-sama to if mag mix kayo ng gasoline. lalo na kung diffrent octane ratings. you might experience engine knocking then worn out na makina mo.. soo..masama to.

go for blaze specially if you have a modded F.I. or N.A. engine.

**Supierreman** · December 3rd, 2003 12:47 PM

Originally posted by jtdc
Petron: Unleaded=93; XCS=95; Blaze=96
Shell: Unleaded=93; Premium=95; Velocity=95
Caltex: Silver=93; Gold=95

meron pa ba iba? yes, meron pa.

sa mga Seaoil, FlyingV, Total, CityOil, etc.

basta unleaded = 93.
pag premium gas nila (iba iba ang tawag)= 95.

yung shell Premium nasa 93 octane lang.

**Karding** · December 4th, 2003 03:12 AM

Originally posted by buddyclub
hmm..mkka-sama to if mag mix kayo ng gasoline. lalo na kung diffrent octane ratings. you might experience engine knocking then worn out na makina mo.. soo..masama to.

go for blaze specially if you have a modded F.I. or N.A. engine.

kapatid, nakaligtaan mo yatang basahin yung isa sa mga replies ko...

like what jtdc said, mixing a 50/50 octane will give you a mid octane rating of the two. Alam nyo ba na most gas stations offering three different types of octane rating usually has two tanks lang? i.e. 87 tank and 91 tank so may middle grade na sila na 89. (very true sa US)

based on my readings also, running higher octane by itself gave no benefit, except to make the fuel harder to auto-ignite, unless you retune your engine.

Check this out.
Mixing Octane Calculator

An info like this one is worth having it as a sticky **ahem** mods