E10 to be the new standard petrol?

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adding ethanol increases octane
But reduces energy content and increases fuel consumption. Octane isn't everything...
 
It looks as though Ultimate 102 is consigned to history as a quick check of the local BP stations only shows Ultimate which I think is 97/98 RON.
The only thing I owned that needed crazy rich fuel was a full supersport Yamaha R6 race bike that needed a minimum of Optimax at the time, but went ran best of all when given some avgas in the tank! ;-)
I don't think Ultimate 102 was widely available anyway, but may well have vanished all together.
 
But reduces energy content and increases fuel consumption. Octane isn't everything...

Quite! Only if the engine can exploit it is it of use. I'm nowhere close to exploiting my 110 RON - though an increase in CR is under consideration.

Even what we might consider highly tuned engines don't necessarily need octane. Honda's bike engines of the 1960s that had tiny cylinders and revved to circa 18,000 rpm only needed 60 RON. Paraffin isn't much higher - if at all.
 
Quite! Only if the engine can exploit it is it of use. I'm nowhere close to exploiting my 110 RON - though an increase in CR is under consideration.

Even what we might consider highly tuned engines don't necessarily need octane. Honda's bike engines of the 1960s that had tiny cylinders and revved to circa 18,000 rpm only needed 60 RON. Paraffin isn't much higher - if at all.
At 18,000 revs/min, octane is pretty much irrelevant.
 
At 18,000 revs/min, octane is pretty much irrelevant.

Combined with tiny combustion chambers, detonation doesn't stand a chance!
On my lowly revving motor with circa 100mm bores, increasing CR to exploit 110 RON is definitely what I should be doing.
 
Given its budget day...

My last tank of diesel cost 119.7p. A little 4th grade maths reveals an effective tax rate of 286%. The diesel itself having a pre tax cost of 41.8p.

So NO I don't think more tax can be justified.
 
I don't think Ultimate 102 was widely available anyway, but may well have vanished all together.

I'm sure I read recently that 102 is still available at a filling station close to Silverstone racecourse - but have no idea which one!
 
Makes for an expensive track day fill-up!! Reminds me of a garage not too far from me that used to be the only one for miles selling unleaded petrol for unconverted cars, at over twice the price of normal unleaded.
 
I was always led to believe ethanol raised the octane rating so don't understand the pre detonation / pinking warning. :oops: It does however lower the calorific of the fuel leading to a slight drop in MPG for your money . Altho touted as a bio-fuel and thus more carbon neutral , ethanol based fuels were historically developed and used by countries who were deficient in conventional geologically sourced hydrocarbon fuels [ oil ] and made sense economically in terms of fuel security of supply.
 
And I thought the Government wanted us all to drive diesels to reduce CO2 :(
 
I was always led to believe ethanol raised the octane rating so don't understand the pre detonation / pinking warning.
Their terminology is a bit suspect. Pre-detonation - do the mean detonation or pre-ignition?

Fuels such as ethanol (eg, methanol) mange to have a high octane rating and thus detonation resistant and be pre-ignition prone.
The pre-ignition requires a 'hot spot' (think methanol in glow plug engines for model aircraft) and ultimately, pre-ignition can create conditions conducive to detonation (eg, high internal temps and over advanced commencement of ignition).

In a high performance application, methanol would be present in such copious quantity ( a consequence of its lower calorific value) that that and its high latent heat of evaporation would suppress the temperature of any 'hot spots' and make pre-ignition unlikely. Less so with a mere 10% blend.
 
I’m guessing E10 is not good news for a W124 era Merc? I usually run the 190 on Tesco Momentum 99, I cant find any info on whether that is planned to change.

Ah, Biofuels - the stuff that is destroying rainforests on a grand scale and accelerating climate change :cool:
That does seem to be reality of anything ‘green’!
 
It seems that E5 will be around for quite a while, and I'm sure the additive industry will quickly come up with solutions. Hang onto your W124 ! My '05 CLK is under threat as well, but I a'int floggin it. :cool:
 
I‘ve not heard of pre-detonation before.

- Normal combustion is not an explosion in the cylinder, but is instead a steady burn with a flame front that spreads across the combustion space at about 50-70m/s. Clearly if the cylinder is only say 100mm or so in diameter, the whole combustion thing doesn’t take long.

- Pre-ignition is caused by hotspots and occurs before the spark. It is not managed by raising octane quality or by reducing ignition timing advance. Cylinder pressures can get very high under pre-ignition and cause damage to the piston, con-rod or bottom-end bearings.

- Detonation/pinking/knock occurs after the spark in the ‘end gases’ and can be managed by raising octane quality (slower flame speed, more resistance to knock) and/or by reducing ignition advance (reduces combustion pressure). Detonation is an explosive event. The gas velocities are maybe 10x normal speeds and that’s what is heard. The very high velocities create turbulence which disrupts the boundary layer protecting the combustion chamber from the full heat of combustion. So during prolonged detonation, things can get a little toasty in there.

Two different combustion phenomena.

Most engines can tolerate some detonation, but it can create hotspots which may then lead to pre-ignition. Pre-ignition under load can quite quickly lead to very serious damage in the engine.
 
There's now a Govt. 'E10 check' website: Check if your vehicle can run on E10 petrol

This is what it says for MB ... bad luck if you have a C200 CGI or CLK200 CGI in that date range:

View attachment 114695

As an aside I notice this product from Aldi requires "Non-ethanol unleaded" ... presumably E5 is ok, but :dk:


So why are CGI engines incompatible with the E10 fuel?

And is the M272 at risk?
 
So why are CGI engines incompatible with the E10 fuel?

And is the M272 at risk?
early example of direct fuel injection [ into cylinder rather than manifold] would suggest materials or clearances of injectors/ high presssure pump incompatable with E10 [ even E5 was a problem iirc] leading to excessive wear or clogging up?? were these CLK's ever sold in the UK?
later design direct injection systems not a problem
 
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