Too low octane - implications??!!

[Toffen]

Hi!

I have just learned that unleaded gasoline of posted octaned rating 92 in US is not equivelent to 92 in Europe. The equivalent in Europe is 98 RON.

I have used 95RON under the impression that this octane rating was higher that 92 US. I should have used 98 RON (super as we call it).

I have seen a tendency to fauling, but this has been minimized by adding carbongueard. What happens when you use too low octane on your engine? It is a Promax 300 EFI 1999 model. The engine has been decarbonized each winter.

What kind of performance gains should be seen using the correct 98RON gas?

Cheers, Toffen G - Norway

[Techno]

I don't know anything about your engine, it might be able to compensate for the low octane(retard timing& knock sensor). Low octane and high load will pit the pistons and heads. The higher the octane, the slower it burns. Otherwise it explodes instead of burning.

Your increase in performance would come about if the engine is retarding the timing in an effort to prevent damage to itself. If it's not adjusting itself to this lower fuel then you won't see a performance change, only less damage to the engine. You would probably notice the engine running differently - pinging if the engine wasn't changing the timing.

[jimmyb]

lower octane will increase the chances for detonation...

detonation will most likely lead to piston failure/engine sticking.

Since you have been running 95RON,(equivalent to 89~90 octane US) things are probably ok. I would definately advise running the 98 RON in the future to make sure you dont have any detonation issues.