Octane curiosity

[Trojan Thunder]

The manual, brochure and dealer all say 91 RON but inside the fuel door it says 95 RON,
I feed it 95 or 98 anyway but thought this was a curious discrepancy. Any thoughts ?

 

[DCBStingerGT]

The manual, brochure and dealer all say 91 RON but inside the fuel door it says 95 RON,
I feed it 95 or 98 anyway but thought this was a curious discrepancy. Any thoughts ?

I believe the Stinger will absolutely run fine on 91, I personally have ever filled it up with Shell V-Power 98.

 

[ShannonC]

Odd that the fuel door states 95. There are various thoughts on what to run but minimum is 91 and consensus in AUS seems to show little to no difference in consumption or performance.

 

[Flameangel]

I run mine on 98 only but my hubby is a fuel Tanker Driver and advised me that 98 is cleaner, more filtered fuel and higher Octane.
95 is good too but does have a waxy additive to it. 91 is okay but considered by those in the know as more of a dirty fuel, less filtered and always leaves debris in the tankers after unloading. If you regularly use 91, it is always a good idea to pop in a tank of 98 now and then to clean up the engine.

 

[DCBStingerGT]

I run mine on 98 only but my hubby is a fuel Tanker Driver and advised me that 98 is cleaner,

98 being a cleaner fuel is what is important to me, and not only in my Stinger, but I run it in my 2004 VZ Commodore, and I know for a fact my Alloytec V6 in my Holden runs better and healthier on Octane 98, economy and power figure gains are so small and virtually non existent , and is not why I use Shell V-Power 98.

 

[Trojan Thunder]

If my fuel card will pay for it I’ll run 98, the detergent packages are great for the engine. Card definitely pays for 95 so I’ll try 98 next time. Car was delivered with 91 in it and ran just fine but if I can use 98 I’d prefer it. No 98 available in town but in Kyneton I can get BP, Caltex and Shell. I’m fond of BP ultimate 98 and use it exclusively in my motorbike.

 

[Cashie]

I only run 95 or 98. have exclusively in all my petrol cars for many years generally due to the reported clean running benefits.

 

[19GT-AWD]

Using less than RON 95/AKI 91 could result in power loss and increased fuel consumption.

 

[crg]

Make sure to check the label in your own country. Engines are not tuned equally and have different requirements in different countries according to local tune, even for similar models.

 

[Kato]

The manual states that outside europe you're good for 91RON. Been running 91 in mine with the odd tank of 95 and 98. The higher octane gets a bit more range (50kms or so) and is nicer when it's hot. Figure if it runs on the cheap stuff that's what I'll get.

 

[Stinger GT SS]

98 only for me, either Shell V-Power or BP Ultimate.

 

[Manaz]

Using less than RON 95/AKI 91 could result in power loss and increased fuel consumption.

View attachment 31271

That's straight from the owners manual in an Australian delivered car.

The fuel filler door does then say RON95:



As well as allowing for E5 and E10. I suspect the sticker on the fuel filler door is generic (E5 isn't a thing here either), whilst the manual is what should be taken as gospel (it also matches the rating that Kia Australia publish in the specs on the local website).

I am conflicted on what to use. Sure, RON98 apparently has better additives, but many of the benefits of the detergent packs in it are moot on a DI engine (because the fuel isn't washing the valves or low-pressure injectors).

RON98 will resist knock better, but a stock tune won't push the timing hard enough that this is likely to be an issue (sure, once tuned, things change). It's basically impossible for a stock tune to get any more power or efficiency out of RON95 or RON98 fuel than it will get out of good RON91 fuel.

RON91 is, right now as I type this, about 25c/L cheaper than RON98 (or to put it another way, about 17% cheaper).

E10 is 2c/L cheaper than RON91. To put that another way, ~1.5% cheaper. The problem here is that ethanol is about 30% lower in stored energy than petrol, so you're down about 3% on specific power (energy per litre) - meaning, all other things equal, you're going to burn about 3% more of it them you would RON91 to go the same distance. I don't know about you, but paying 1.5% less to go 3% less distance doesn't sound like good economic sense to me, unless you're a politician with money invested in ethanol production and you've managed to pass laws mandating that a percentage of all fuel sales must be E10...

 

[Cashie]

My MY18 fuel door says this:

 

[Cashie]

I am conflicted on what to use. Sure, RON98 apparently has better additives, but many of the benefits of the detergent packs in it are moot on a DI engine (because the fuel isn't washing the valves or low-pressure injectors).

If you can believe the petroleum companies at all, they also claim other benefits such as f(r)iction reducers and rust inhibiters. I'll continue to use 98 and 95 when 98 isn't available.

 

[Manaz]

If you can believe the petroleum companies at all, they also claim other benefits such as fiction reducers and rust inhibiters. I'll continue to use 98 and 95 when 98 isn't available.
View attachment 31377

They don't lie about what is in the fuel (they'd get in trouble if they did), but they certainly overstate the benefits.

Sadly, fiction reduction is about the last thing they'd include.

Friction reduction is taken care of by oil. The development of rust anywhere in the fuel system is something that fuel additives are going to influence - fuel itself will prevent that.

 

[OliverNuther]

they also claim other benefits such as fiction reducers
View attachment 31377

Fiction reducers would make this whole issue a lot easier. (I know, I know, typo but still funny)

 

[Cashie]

Sadly, fiction reduction is about the last thing they'd include.

They certainly claim they do (hence the jpg I included off their website).
Whether it works or not who knows..


Edit--> lol just saw my typo.

 

[ShannonC]

My MY18 fuel door says this:
View attachment 31376

Same sticker on mine, although I thought I saw 91 somewhere...maybe in the OM.
initially I ran 95 but have been on 91 for nearly 9 months or so with an occasional fill of 95. Can't say I've noticed any difference except in price.

 

[Trojan Thunder]

Here’s my MY 19 fuel door, I’m sticking with 95 or 98

 

[ShannonC]

Must have changed sticker from 18 to 19.