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Quick report -

so far done about 220kms, used about 35 litres of the stuff! Shitehouse economy! Maybe the oxygen sensor for the ECU can't tell its got 10% more ethanol in it, much the same of the dyno's...... so its adding a extra 10% to light load cruise?

Knock levels about the same

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The O2 sensor doesnt know that you've got ethanol in it, but it will detect the leaner mixture and the ECU should compensate somewhat.

Ethanol has a lower calorific value than petrol, so basically the SAFF stuff (or any other ethanol mixed fuel) has less 'bang' or energy for the same amount of petrol. Thats why your economy is suffering, and is one of the major downfalls of ethanol mixed fuels. Usually the economy drop is roughly 2-3% in most cars for a 10% blend. If you're suffering much more than that, then something is wrong...

So IMO the bottom line is that you're not really saving money on ethanol fuels, unless its able to at least compensate on the pump price with respect to the fuel economy loss. That means roughly 5c/L cheaper. I'd have no problems using it in your average 10 year old car I guess, but I dont see the point using it in our cars.

Edited by Busky2k

that's what I thought too busky

Your car will only use more fuel in closed loop ie cruise/constant speed where the ecu detects leaner condition and add extra fuel. In open loop it won't know which fuel is in there.

The added avantage of this fuel is better knock retardation. So you can run more boost/timing safer. If you want more power you wil have to fill up more frequently :D It's part of the game unfortunately.

Well over all, I got 370kms out of a tank. The last hundred odd kms was just off boost driving around really.

Economy wise it went pretty close to what I usually get out of a tank of BP/Mobil, maybe 30kms less

I'd say overall, its not any better in regards to performance, knock levels where pertty similar.

I guess the jury is still out, need to do a bakc to back dyno to see if its any better

But, from what I experienced, if you where stuck, and needed to fill up, it would do the job pretty well

Hmmm. The only issue I have in terms of 'knock retardation' etc is that if the petrol is rated at 98 RON, is it tested including the ethanol? If 2 fuels are 98 RON rated, and one is ethanol blend, then neither should have advantage over the other.

SAFF would theoretically allow MORE timing if they start with a 98 RON base and add ethanol, rather than a 96 RON base and then adding the ethanol to make up to 98 RON. (Ethanol has an octane rating of ~110) Might be worth firing off an email to SAFF to see which option they take to make their 98 stuff.

Edited by Busky2k

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