just been reading this if anyone else may find it intresting.

http://www.superstreetonline.com/how...s-engine-tech/

 

Interesting, but being written by an American for the USA market, assumes that American tuners a) know best and b) are the only ones out there.

The longest running of those tuners has only been involved with "Subies" since 2003. LMAO.

 

They have the 2.5 l units as well

 

Interesting read.

Do US tuners suffer from low octane fuel? The article mentions 91octane where in the UK we are using 99 (Japan is 100 iirc).

 

The numbers aren't equivalent between the US and the rest of the world. Taken from wikipedia:

Difference between RON, MON, and AKI[edit]

Because of the 8 to 12 octane number difference between RON and MON noted above, the AKI shown in Canada and the United States is 4 to 6 octane numbers lower than the AKI shown elsewhere in the world for the same fuel. This difference between RON and MON is known as the fuel's Sensitivity,[4] and is not typically published for those countries that use the Anti-Knock Index labelling system.

 

So essentially 91 octane in America is like normal super unleaded (97) and 93 is like Vpower (99).