Different brand of fuels?

Some months ago (before joining the Ghetto) I fitted a rock strainer (K&N) and had Bella re-dyno'd, properly.
Shortly thereafter I noticed a bit of a knocking sound emanating from under the tank, I put it down to air intake pulsations/harmonics.
It would only happen under light load cruise mode in town. Also was using BP 95 octane exclusively. (I know pinging & big end failure from experience)

Tried a foam block between tank and frame behind steering head. It was quieter but noticed economy had dropped from 5.3 to 6.0l+/100k.
Removed foam block but noise and poor economy persisted for several months, using BP 95.

Yesterday I was forced to fill up with Shell 95 octane. Cruising between 90 & 120kph to my rendezvous with Plantboy, I noticed an average of 4.8l/100k.
Gil had a play in the twists and it dropped to 5.4l/100k. Kieran and I both had a play as well with average for this tank remaining at 5.4l/100k.

On the return journey steady cruising saw the av. drop to 5.1l/100k. Never seen these low figures before, ever.
I tried duplicating the harmonics and pulsations in the air box, can't.

Is this purely a coincidence, as in I have an intermittent sensor fault (no codes) or these fuel companies messing about with their product?

Interesting Wayne,

I only use Shell 98 (or 95 in a pinch if they don't have the good stuff) in my Sport and seem to get good results. I have tried others but I know some of the other brands were importing their premium fuels from wherever and quality control has been ordinary at best. I have been warned away from Caltex by my car supplier (Hyundai) for a number of reasons.

Some time back, I received a discount at Caltex and filled up my car there for a few tanks. Still 98 octane but consumption went from 9.0-9.1 l/100km to 9.6 - this for supposedly identically rated fuel which may lend credence to what Hyundai told me. Discount ran out and I stopped it before I went blind...

In the past I have tried BP and the other mainstay brands (though they are few and far between these days) only out of desperation when normal supplies of Shell 98 are not available. I avoid the "no name" outlets like the plague as I have on good authority the deeds that go (largely) undocumented through these outlets.

Funny, I had forgotten the "other" fuels even existed, I am happy with the Shell product, though it is no longer created in Sydney, and maybe not in Oz at all - but the quality seems to be still consistent.

Other experiences???

I've used 'em all. I was a regular Caltex user (98 Octane) without any issues at all. When away from home I always sought a Caltex servo. If they didn't have 98 Octane, I'd go to a Shell or BP. No issues with any of them at all. I now use the local no-name (Foobar/Liberty/Dodgy Bros) and she still runs like a champ.

I wish we got 98 octane here in the US...

I think the difference in quality fuel has more to do with the station itself, not the brand.
If poor maintenance of the tanks by a particular station occur, then you'll have contaminants in the fuel and the customer gets screwed.
It happens a lot in the US with Marine fuels.
There are even scams where they dilute the fuel in order to stretch the Dollar at the customer expense...

Maybe Wayne got contaminated fuel from that station on that particular tank, who knows.

Yeah. The best I get is 91 octane and that is all I put in my GRiSO.
I also run those fuel injector cleaners thru my tank about every month or two.

DM

There was a time IIRC that all fuel on the east coast of Oz came from two or three refineries only (Caltex and BP). The only difference was the additives the various companies put in. If you got crap fuel generally it was a bad tank or dodgy retailer.

BP closed one recently and so did Caltex. Caltex is going to close their second one soon too. We'll be dependant on overseas refineries for more than 50% of our fuel soon. I fully expect crap fuel from time to time then.

Welcome to Tasmania.
There's one set of fuel bunkers for all the brands, octanes and stations.
All run by BP.
Sometimes the blend isn't perfect, usually at between season time.
A small price to pay for the roads on offer.

To add
They just overhauled my local Caltex ,
The 91 fuel no longer states ethanol content or contains ethanol. Says 91 no longer E10
I know the family 2006 Corolla would not run smoothly on the E10 especially in the freezing Sydney winters of 16 deg C. Had the car serviced and 2 local mech work shops said E10 fuel is the cause so we changed to RON 95.

Will try the 91 again soon but its interesting to see it gooone

You have ethanol in Australia now!?  These big corn companies are a cancer that just keeps spreading. Over here they're trying to increase the ethanol content to 20%. It seems they won't rest until every engine on earth is a sputtering heap of shit!

Ethanol seems to have taken a nose dive here. Can't keep up production or not enough sugar .......................

E10 is subsidised by the govt here (about 4c/litre) but as soon as the masses are sucked in the price will spike. Few years ago they offered a $2000 rebate for people to fit LPG to their cars. As soon as they reached a nominated figure the subsidy was removed and then quickly followed by a 30c/litre price hike.

Now tell me Wall Street isn't just a shonky Casino run Mafioso style, with the decks continually stacked against the average punter.

ghezzi wrote:

Ethanol seems to have taken a nose dive here. Can't keep up production or not enough sugar .......................

E10 is subsidised by the govt here (about 4c/litre) but as soon as the masses are sucked in the price will spike. Few years ago they offered a $2000 rebate for people to fit LPG to their cars. As soon as they reached a nominated figure the subsidy was removed and then quickly followed by a 30c/litre price hike.

Now tell me Wall Street isn't just a shonky Casino run Mafioso style, with the decks continually stacked against the average punter.

Aussie ethanol is/was mostly made from wheat, not sugar.  Company called Manildra (sp?) part owned by little Johnny Howard's brother was a  director I believe.  All a big con.