Should you always adhere to your manufacturer's recommended octane rating?

**valacirca** · September 10th, 2012 06:48 PM

(FYI: I currently drive a 1.4 AT EX Kia Rio Sedan. This thread is just an offshoot of a discussion sa Kia Rio thread.)

Ang recommended octane rating kasi for Gamma engines - like the ones used by Kia and Hyundai - is RON 95.

Na-mention ko sa Kia Rio thread that I've used Shell Fuel Save (RON 93) since buying the car a little over a week ago. I chose Shell mainly for convenience since I pass by a lot of Shell stations to and from work. And I chose Fuel Save as recommended by friends and relatives based on their experience and kasi hindi naman daw kailangan ng Rio ng gas na malakas.

The most common problem of the Gamma engine with low-octane fuels is engine knock; but so far, I've used Shell Fuel Save for over a week without any problems. However, the people on the Kia forums still advise that even though I'm not experiencing any problems now, magkarga pa din daw ako ng fuel with a higher octane rating (like Petron XCS, which has an octane rating [RON 95] exactly like that recommended for the Gamma engine) just to err on the side of caution. Para din maka-iwas ng possible problems in the long run.

Ang mga tanong ko lang:

- Is it really advisable for my specific scenario that I change the type of fuel that I put in my car?

- If I must choose between a higher or lower octane rating, which should I choose? Kasi ang Shell for example, wala silang RON 95... meron lang sila RON 93 and RON97... Considering ang recommended for the Rio is RON 95, alin dun sa RON 93 vs RON 97 ang mas safe piliin for the car?

Thanks!

**7138** · September 10th, 2012 07:26 PM

do as what your manual recommends,

if the MINIMUM octane rating for your car is 95, the term speaks for itself,
higher than minimum is much better than the lower rated ones.

pero sir, its your car,
decision mo naman yan, if gusto mo talaga yung lower than recommended octane,
then do as you wish.
pero pag meh nadali, dont blame the dealership (kia) na nagkulang sila sa paginform sayo,
nakasulat naman na sa manual ang minimum is 95.

**Retz** · September 10th, 2012 07:30 PM

*valacirca,

Choose Petron XCS/Blaze or V-Power Nitro+Racing. Basta equal or greater than 95 RON. Saan ka ba based?

**userfriendly** · September 10th, 2012 07:31 PM

Using a lower octane fuel can result in engine knock. Constant engine knock can lead to engine damage. Its perfectly safe to use a higher octane rating than required by your manufacturer. So you can use 95, 97 or even 100 RON fuel. But I wont recommend using 93 octane (RON)

**lowslowbenz** · September 10th, 2012 07:34 PM

If your car is still under waranty, which I think it is, stick to what your manufacturer says.

You would'nt want to be at the losing side when it comes to warranty issues brought about by using incorrect fuel.

Toyota recommends a minimum of 93 RON for the Vios, so that is what we use!

**valacirca** · September 12th, 2012 02:32 PM

Thanks guys. On my next gas-up, I'll load the car with Petron XCS.

Although intriguingly, the manual of the Kia Rio has this to say regarding fuel:

For Europe: For optimal vehicle performance, we recommend you the use of unleaded gasoline which complies with EN 228 and has an octane rating of RON (Research Octane Number)95 / AKI (Anti Knock Index) 91 or higher. You may use unleaded gasoline with RON 91-94 / AKI 87-90 but it may result in slight performance reduction of the vehicle.

Except Europe: Your vehicle is designed to use only unleaded fuel having an octane rating of RON 91 / AKI 87 or higher.

So idk... obviously we are not in Europe. Does this mean I can feed the Rio fuel with an octane rating as low as RON 91?

**lowslowbenz** · September 12th, 2012 02:45 PM

Originally Posted by valacirca

So idk... obviously we are not in Europe. Does this mean I can feed the Rio fuel with an octane rating as low as RON 91?

Do you really wanna risk it? Even the tricycles load on XCS, Gold, Super Whatever fuel, etc. And you want 91 octane on your car?

**vinj** · September 12th, 2012 03:00 PM

Originally Posted by lowslowbenz

Do you really wanna risk it? Even the tricycles load on XCS, Gold, Super Whatever fuel, etc. And you want 91 octane on your car?

True... my beater B13 Sentra with a carb engine get loaded with XCS always as it runs much better as compared to when it uses 93 octane. Performance is better and i can get up to 1km/L more in my city drives (9-10km/L with XCS vs. 8-9km/L w/ xtra unleaded).