Here in the uk we use 95 or 97 octane petrol where as you guys use
93, 91 And 87 Octane.
I suggest that if you moved to a different octain leval you would have to retune (Ignition timing) for the new Octane level.
Have a read of this
USATODAY.com - Why use premium gas when regular will do?
93, 91 And 87 Octane.
I suggest that if you moved to a different octain leval you would have to retune (Ignition timing) for the new Octane level.
Have a read of this
USATODAY.com - Why use premium gas when regular will do?
Lindvm colonia
New Member
That is enlightening, I didnt realise they used 'pool petrol' the other side of the pond.
92 RON cheapo nasty unleaded is the equivalent of our old 2 star so 89 RON must be quite awful.
No wonder they need 7 litre engines over there
92 RON cheapo nasty unleaded is the equivalent of our old 2 star so 89 RON must be quite awful.
No wonder they need 7 litre engines over there
Lazy Landy
New Member
Think what would happen if you put one o'them 7 litre jobies on real fuel then.
**** all!! yer octane rating is to do with yer fuel not detonating before the spark plug sparks. the higher yer octane rating the higher compression you can run. so to get any benefit from a high octane rating you'd need to, at the very least, skim yer heads.
there more to it than that but as i dint like to witter on to much thats all yer getting.
if you want more info put a request in fer a anorak!
eightinavee
Well-Known Member
You might want to rethink that one Slob.
Lazy Landy
New Member
I thort the highter the octane rateing the bigger the bang.
why's that then???
The octane rating is a measure of the autoignition resistance of gasoline (petrol) and other fuels used in spark-ignition internal combustion engines. It is a measure of anti-detonation of a gasoline or fuel.
Octane number is the number which gives the percentage, by volume, of iso-octane in a mixture of iso-octane and normal heptane, that would have the same anti-knocking capacity as the fuel which is under consideration. For example, gasoline with the same knocking characteristics as a mixture of 90% iso-octane and 10% heptane would have an octane rating of 90. [
Take5
New Member
That is true, but getting more power out of a yankee injun on high octane is a bit more complicated than advancing your ignition timing by 5 degrees. In order to get the most out of it, you will need to increase compression ratio as well to fully realise the fuel's potential - skim the heads like M. Slob said.
Running on LPG is a bit like running on 105 AvGAS as far as ignition timing is concerned, hence when running on LPG with standard timing you see a big performance and economy drop. One way round is to advance your ignition timing with a skimmed high compression head, and you have similar performance/economy on GAS and unleaded. However, you will have to run 98RON Petrol with about a 5% Butanone or Propanone mix (nail varnish remover, MEK Solvent etc) to avoid detonation when running on Petrol. Should go quite a bit better as well
Anyway, enough sensible techie stuff, I'm orf to the pub to get ****ed soon
