What RON fuel do you run in each of your cars?

[Dyldo]

well its a vr6, the fuel cap says to use 95 or something, and idk if thats meant to be 95 in uk standards or what, eitherway 98 seems to make it happy

Your probably right and it makes little/no difference, but that further goes to show that on here your just going to find a load of vw crazed people who will only want to give there cars the best, unlike someone who just sees there car as a way for a -> b

Hell, if 98 makes her happy then run 98. I personally run 95 in my Bora because I remain convinced that the 98 is a waste as my Bora is not tuned for it. I have read up on the subject, and the basic facts appear to be that in a car with a modern engine management system then as it detects a higher RON value it advances the timing to compensate. The reverse is also true, in that if the engine detects pinging or knocking (typically lower RON value in the fuel) it will retard the timing to prevent engine damage.

A huge misconception is that RON = power. Simply not true. The RON value is created/altered at the refinery by changing the chemical make-up of the fuel (all fuels are just a cocktail of hydrocarbons anyway) and then they add cleaners and surfactants etc. Basically, a good engine management system will advance timing till detonation is detected and then retard so there are no knocks detected.

Clearly from the pools the winner is 98, which is understandable and indicative of the love we throw the way of our Frauleins. I can't help but wonder though of the wasted "potential" of the fuels we use. I.e. we love our cars so much but don't go and get the ECUs tuned to run 98 to take FULL advantage of the fuels we get (not a lot of countries get over 91, and 95 in the US is their Super-Premium fuels. In fact they run e85 but thats a whole other thread

Most chips/tunes specify 98RON I believe (and the tunes make use of the extra octane level by running increased timing). I know the CC tune for my car requires 98RON (so I'll be back on it regardless once I finally get the car tuned).

I am so taking your Bora for a run with the CC tune. yum.

[brad]

A
. I.e. we love our cars so much but don't go and get the ECUs tuned to run 98 to take FULL advantage of the fuels we get (not a lot of countries get over 91, and 95 in the US is their Super-Premium fuels. In fact they run e85 but thats a whole other thread

The US measures their fuel using the MON (Motor Octane Number) rating system. It gives a lower number than our RON rating. Japan has 100ron readily available & 99ron is common in the UK.

Also, octane numbers don't take into account the other components of a fuel - eg: sulfur levels

Also, ROn rating doesn't take into account