3.3 TT OEM tune does pretty well with race gas

[rpoffen]

To be clear, this doesn't require an engine tune? The stock ECU calibrates for E85?

Doesn't require it, but there is no real need unless you use at least a piggyback tune like a jb4.
You can get ECU tunes for it also. You really only need the higher octane when increasing boost.

 

[5tinger]

In Australia the octane rating at the main suppliers go like this e10 > 91 > 95 > 98

E10 is a laughable joke, costs about $0.02 less than regular, yet you lose 20% MPG in addition to the adverse effects of the ethanol mix.

91 is the standard unleaded.
95 & 98 octane contain higher detergency and lower sulphur levels.

 

[rpoffen]

In Australia the octane rating at the main suppliers go like this e10 > 91 > 95 > 98

E10 is a laughable joke, costs about $0.02 less than regular, yet you lose 20% MPG in addition to the adverse effects of the ethanol mix.

91 is the standard unleaded.
95 & 98 octane contain higher detergency and lower sulphur levels.

Here in the states, virtually all gas is e10.