Originally Posted By: Pontual
I was reading this yesterday and did 5% in my Ninja ZX9R, with 12 to 1 CR. Run 150 miles without any difference. Tip of exhaust got a litler darker and thats it. 10% maybe feseable, but thats with you. I believe that at 5% it would burn lubricant 2 or even 4 stroke, imagine fuel (diesel)...
Diesel octane range is given as "about 15-25" here (but gives no source for the number)
http://www.madsci.org/posts/archives/2000-10/973012182.Ch.r.html
and here in this thread
http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/272893/Re:_Octane_rating_of_diesel_fu
which also gives a range of 8-15 in another post. Sources are given, but I can't find these numbers in them.
The scale used isn't given, but I assume its the US AKI scale rather than the RON scale used almost everywhere outside the US.
This (8-25) is a fairly wide range, with 16.5 as its mid-point.
In the abscence of any other info, I'd assume the octane of a mixture is a simple arithmetic mean of the octanes of its components, though I have heard there MAY be some exceptions, as when mixing leaded and unleaded petrol, so this assumption may not be valid for the extreme case of a diesel/petrol mix.
The fuel used is not given in the above post. Assuming its 94 AKI,( which I believe is the highest octane generally available in the US?) I THINK the resultant octane of a 5% mix of diesel at 16.5 octane would be given by:-
=((95*94)+(5*16.5))/100 = 90.125?
It is of course trivial to put this (probably simplistic and quite possibly wrong) formula in a spreadsheet so you just have to enter the values.
10% diesel gives 86.25, which I'd guess many modern engines could easily cope with by altering the ignition timing under control of the knock sensor.
If the diesel is at the upper end of the quoted octane range, (25) a 10% mix is 87.1 AKI.
If the diesel is at the lower end of the quoted octane range, (8) a 10% mix is 85.4 AKI
I was reading this yesterday and did 5% in my Ninja ZX9R, with 12 to 1 CR. Run 150 miles without any difference. Tip of exhaust got a litler darker and thats it. 10% maybe feseable, but thats with you. I believe that at 5% it would burn lubricant 2 or even 4 stroke, imagine fuel (diesel)...
Diesel octane range is given as "about 15-25" here (but gives no source for the number)
http://www.madsci.org/posts/archives/2000-10/973012182.Ch.r.html
and here in this thread
http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/272893/Re:_Octane_rating_of_diesel_fu
which also gives a range of 8-15 in another post. Sources are given, but I can't find these numbers in them.
The scale used isn't given, but I assume its the US AKI scale rather than the RON scale used almost everywhere outside the US.
This (8-25) is a fairly wide range, with 16.5 as its mid-point.
In the abscence of any other info, I'd assume the octane of a mixture is a simple arithmetic mean of the octanes of its components, though I have heard there MAY be some exceptions, as when mixing leaded and unleaded petrol, so this assumption may not be valid for the extreme case of a diesel/petrol mix.
The fuel used is not given in the above post. Assuming its 94 AKI,( which I believe is the highest octane generally available in the US?) I THINK the resultant octane of a 5% mix of diesel at 16.5 octane would be given by:-
=((95*94)+(5*16.5))/100 = 90.125?
It is of course trivial to put this (probably simplistic and quite possibly wrong) formula in a spreadsheet so you just have to enter the values.
10% diesel gives 86.25, which I'd guess many modern engines could easily cope with by altering the ignition timing under control of the knock sensor.
If the diesel is at the upper end of the quoted octane range, (25) a 10% mix is 87.1 AKI.
If the diesel is at the lower end of the quoted octane range, (8) a 10% mix is 85.4 AKI
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