Myths about the fuel we use in the philippines

[vinj]

yup. forgot to mention that. meron naman knock sensor so if you use lower-than-recommended octane gas the ECU will detect knock and retard ignition timing to eliminate it but it results in sluggish engine performance

On the other hand, you can also get slightly better response by advancing the timing on the car from the stock setting and using higher octane fuel. Thus, is it safe to say that it's not the fuel per se that's responsible for the power but rather the adjustments the engine makes as a result of the type of fuel used?

[uls]

^^^^

yup that's right

[niky]

Most cars can handle gasoline that's slightly worse than they're programmed for, but sluggish performance and poor economy are a real possibility.

Even worse, I was talking to a fuel engineer, and in his opinion, certain companies had knock sensors and learning algorithms that really can't deal with poor fuel. Which explains the widespread complaints of knock you might see elsewhere in this forum.

This is to say, the ECU can deal with low octane, but only up to a point before it enters a nasty feedback loop and can't pull enough timing to cope. This is similar to the problem wherein some ECUs can't cope with that tiny extra bit of air from the Khaos Super Turbo Charger air-bleed device.

And then there's still the problem with varnishing and contamination. Certain high-end brands which use gasoline direct injection get a lot of customers in the shop who need their fuel systems purged and clean. because they don't cycle the E10 in their tanks often enough. Hell, I lost one fuel pump to E10 contamination myself. (rubber disintegrated completely, because I didn't cycle the fuel in the tank as I was on LPG more often)

[Bitulo]

I just want to rant and get it off my mind....

This is just me but one thing I keep hearing is that our fuel is less pure compared to those abroad. And these people would say that it is the reason why our fuel can't be used for imported cars, that you should use the special fuels with the better blend, etc. A epiphany I noticed was just my recent vacation in LA, I needed to gas up the rental car and I noted that the highest octane rating for their fuel is 87. Here in our country, our fuel rating is around 95-97 percent. In fact I never saw even in chevron (caltex) or any other gas station a fuel rating greater than 90 (it seems they add ethanol in higher concentrations to their gas) anywhere in LA, and I mean from Pasadena down to San Diego. So now I find myself laughing and grinning when people posts that the lower blend fuel in our country (usually 93) causes their "engine to knock", "have a lower pull", poor response time", etc. Driving around LA never made any noticable changes to engine performance (and this is freeway running at around 65 to 80 mph/ 100-120 km/hr) despite the fact the car (a honda 2010 CIVIC) used a 83 blend from shell. I guess people tend to be gullible to those marketing strategies...

Fact 1 - octane number is an indication of the ability of the gasoline to prevent knocking of the engine. The higher the octane the better the ability of the gasoline to prevent knocking. Generally, higher compression ratio engines have a higher minimum octane requirement. But in the Philippines, majority of the cars have compression that is satisfied by a minimum of 91 Research Octane Number.
Fact 2 - your car's manual states the minimum octane number that your car can take. If your manual says minimum of 91 Research Octane Number (RON), then you should use a gasoline with an RON not lower than 91, or else it will knock. You may however use higher RON without the engine knocking.
Fact 3 - present day computer controlled engines operate such that the computer always automatically and instantaneously advances the engine's spark timing up to the point of slight knocking. So if you use a higher RON like 95, the computer automatically advances the timing some more, up to the point where there is very slight pinging and this advance will give more power. If however you have a gasoline with a lower RON, say 92, the computer retards the timing appropriately thus resulting to lower power.
Fact 4 - it is true that another octane rating is the Motor Octane Number (MON), but here in the Philippines, we use RON in our gasoline labels and in the car manual. The important thing is that the basis of comparison is consistent - meaning RON in the manual compared with RON in the gasoline label. If your car came with a MON gasoline specs, then you should find a way to convert the MON into the equivalent RON. By the way, the MON testing is done under a more stringent testing condition, and this used more often in testing aviation gasoline (Avgas)
Fact 5 - in the older engines with carburators, the advance timing is manually set everytime we use another octane number in order to take advantage of the additional power afforded by higher RON. If we do not manually advance the timing, the higher octane has no benefit at all.

I hope this gives some enlightenment to our Tsikoters.

[frenchtower]

I just want to rant and get it off my mind....

This is just me but one thing I keep hearing is that our fuel is less pure compared to those abroad. And these people would say that it is the reason why our fuel can't be used for imported cars, that you should use the special fuels with the better blend, etc. A epiphany I noticed was just my recent vacation in LA, I needed to gas up the rental car and I noted that the highest octane rating for their fuel is 87. Here in our country, our fuel rating is around 95-97 percent. In fact I never saw even in chevron (caltex) or any other gas station a fuel rating greater than 90

Just a correction. We have 91 in California

[HonestTruth]

is shell fuel save a myth???

[olidotcom]

is shell fuel save a myth???

good question sir.. hope somebody can answer.. but from my previous experience.. i always use Shell Fuel Save.. but few months back when my suking gas station was offering same price for their next level Shell Gasoline.. (forgot the product) I observed that my fuel consumption went bad.. Haven't tested it again since tipid mode tayo :D