Isn't that what I was getting at? I thought it was.
I love the disclaimer!
Might it have been one of the fuel companies I mentioned?
And was that advice well received? And acted upon?
Diesel vs Premium Diesel
- Thread starter BlindFreddie
- Start date
Might it have been one of the fuel companies I mentioned?
And was that advice well received? And acted upon?
Hi.
I don't have any hands on experience with the vehicle you mention, you do. So in light of your credibilty here, I accept at face value what you say.
But I would be interested, knowing your technical background, why you think the engine delivered that result?
What was the specified RON for that vehicle?
Cheers.
My Berlingo test was between E10 (which the sign on my servo says is 95RON) and Shell 98. No measurable difference whatsoever.
As to ECUs, knock sensors have been around for a while, my '89 SAAB Turbo had one.
I remember Wheels tested the first Aus market Volvo Turbo 760 198?. Its acceleration tests were identical to the aspirated version. Somehow they worked out someone had put normal unleaded in it (premium was recommended) and they subsequently filled it with premium, and the 1/4 mile dropped by over 1 second. It was just retarding the timing when it had standard fuel in it.
As to ECUs, knock sensors have been around for a while, my '89 SAAB Turbo had one.
I remember Wheels tested the first Aus market Volvo Turbo 760 198?. Its acceleration tests were identical to the aspirated version. Somehow they worked out someone had put normal unleaded in it (premium was recommended) and they subsequently filled it with premium, and the 1/4 mile dropped by over 1 second. It was just retarding the timing when it had standard fuel in it.
And that is exactly my point. Modern ECUs have the ability to turn down things when knock is detected as a means of protection, so they often run fine on the cheaper juice. Just slower and using more fuel....
But there is deck all advantage in using an octane above the factory tuned level - there is no God Mode hidden in the MAP that allows it to turn it up to 11 when it detects the magic juice. It will simply observe that there is no knock as it would expect from 95 for example and not do anything differently. And given the energy content of 98 is the same as 95 and 91, you get no extra bang.
I've had similar experience at both Yass and Goulburn. The high flow pumps there have the larger pump nozzles and definitely won't fit into a 308.
Cheers
Justin
9.5:1 and cat, so it had to run on 91 via emission laws of that time. Even back in 1991, Motronic ECU’s had a knock sensor, which advanced/retarded the ignition timing. Thus under light load it had the ability to add more timing until the onset of knock, which of course improves fuel economy considerably.
Friend of mine bought a Volvo (240?) with a high compression engine (late '80s/early 90s?), which had the same problem - by law it had to use lead-free fuel, but only ULP (91 octane) was available. When he was finally able to fill it with PULP/95, all the problems disappeared - power and economy both improved.
Avgas is expensive and tends to foul the plugs. Engine (Rotax) is designed to use both. 95 'should' be ok, but we try to be a little conservative and use 98. Now only to hear that 98 is prob 96!
When you say "foul" is that lead particles bridging the plug gap?
My i30 CRDi has the hi-flow filler for its 50L tank. Filling is very quick and I look good doing it in a semi-trailer bay.
Hi
These three anecdotes all illustrate the point made in my last paragraph of post #35. Due to external constraints, the engines were running on lower than ideal (Europeon specified) RON petrol. When the engine was supplied with the RON that they were designed to run on, the performance and also economy improved.
I know I am labouring the point, but its important to get the cause and effect the right way around. It wasn't the higher RON petrol that improved the engine performance, it was because the engine was running on the lower RON petrol that resulted in reduced performance and worse fuel economy. The higher (correct) RON enabled the ECU to characterise the engine to perform as it was originally designed.
Cheers.
I discovered that my son and daughter in law were confused by the labels inside the fuel filler outer cover on their VW Polo (999cc turbo petrol) - one sticker said 95 min, the other said E10 compatible. They went with E10 (cheaper). When I borrowed the poor little thing I found it barely driveable - no power at all at low revs, and constantly stalling on take off unless you revved it and slipped the clutch.
A tank full of 98 (had to dilute the last of the E10) and a good long blast up the Hume and it was fully recovered, much more tractable and easier to drive (and ironically probably cheaper to run on the right fuel). My son chose it rather than a Jap or Korean equivalent as he found it so much more enjoyable to drive - shame to spoil the fun because of fuel confusion...
A tank full of 98 (had to dilute the last of the E10) and a good long blast up the Hume and it was fully recovered, much more tractable and easier to drive (and ironically probably cheaper to run on the right fuel). My son chose it rather than a Jap or Korean equivalent as he found it so much more enjoyable to drive - shame to spoil the fun because of fuel confusion...
That was the result I was anticipating from my Berlingo when I put the first tank of Optimax in it.
Alas after a couple of tanks and plenty of thrashing nothing happened.
One of the local small chain servos used to offer a premium 98 RON E10, which I presume was 95 premium unleaded diluted with 10% ethanol.
Wasn't "cheap" though, and now they no longer keep it.
Interestingly the '89 SAAB Turbo I used to own had adjustable parameters on the ECU.
There were 3 potentiometers that were accessible after removing a cover on the LH inner guard. One was for maximum boost, one was for the rate the boost increased at, and the 3rd was the knock sensor's sensitivity.
I was on a UK modified SAABs website, and it said slowly tailor the boost ones to "taste" but "do not touch the one marked K unless the vehicle is being load tested on a dyno".
Of course the 2 boost one I immediately turned clockwise to the stops.
This was the last thing I did (after many other mods and the difference was profound, (some might say dangerous
), but anyhow wheel spinning, torque steering and the subsequent changing lanes of its own accord through the first 3 gears, up to 100 odd KPH suited me just fine.
That was on 95 and I presume on a dyno on 98 and bit of fiddling with the knock sensor, a little more HP would have been available.
He probably had the European tune in it. It would have pinged like crazy on our local fuel. The 16valvers in there time were a quite high state of tune for a mass produced vehicle. The european ones had quite remarkable perforance. The local ones were detuned quite a bit to cater for our crappy fuel.
Interestingly the '89 SAAB Turbo I used to own had adjustable parameters on the ECU.
There were 3 potentiometers that were accessible after removing a cover on the LH inner guard. One was for maximum boost, one was for the rate the boost increased at, and the 3rd was the knock sensor's sensitivity.
I was on a UK modified SAABs website, and it said slowly tailor the boost ones to "taste" but "do not touch the one marked K unless the vehicle is being load tested on a dyno".
Of course the 2 boost one I immediately turned clockwise to the stops.
This was the last thing I did (after many other mods and the difference was profound, (some might say dangerous
That was on 95 and I presume on a dyno on 98 and bit of fiddling with the knock sensor, a little more HP would have been available.
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H'mm. I wonder if the Italian tune up on "...the long blast up the Hume...", was the main reason of improved engine tractability and not so much the change of fuel???
From memory E10 is RON 95 (+/- 1) matching the specified fuel, so should be OK in terms of performance. Due to the typically 3% lower calorific energy of E10 the vehicle would need to consume 3% more fuel by volume to achieve the same performance.
I have never used ethanol based fuels. Not because they are technically inferior, but mainly because they have more susceptibility to pick up water and maybe other contaminants due to poor fuel handling and storage, and potentially degrade earlier than petrol during storage.
Cheers.
I'm sure the long run (several hundred km) must have helped, but most of the improvement was apparent quite quickly. Did 150 km before refill - didn't seem to help much.
If octane rating is quoted for E10, it is usually 94 - not quite 95, but you're right, it shouldn't matter, and my 605 (PRV V6) and Xantia (Turbo CT) used to run perfectly well on the stuff. Makes me wonder if one of them had given it a gut full of ULP (91) - perhaps the servo they went to didn't have E10, and the PULP seemed v. expensive.
If octane rating is quoted for E10, it is usually 94 - not quite 95, but you're right, it shouldn't matter, and my 605 (PRV V6) and Xantia (Turbo CT) used to run perfectly well on the stuff. Makes me wonder if one of them had given it a gut full of ULP (91) - perhaps the servo they went to didn't have E10, and the PULP seemed v. expensive.