You're right Dean, fuel is not a catalyst. It is consumed. My statement is not totally accurate. Let me clarify:
On a
turbo car the fuel isn't the primary power adder. The high density air mass created by by the forced induction is what allows a small displacement motor to make a lot of power, i.e. an "artificially" high compression ratio. Because of this, the ECU needs to supply an appropriate amount of fuel to match the dramatically varying amount of air that occurs at the boost level changes. In order to provide adequate cooling to combat the high temperatures of a forced induction motor, generally a rich AFR is used, as fuel is a cooling element in the cylinder. If you allow more air to enter the combustion cycle than the ECU thinks is entering (aka aftermarket intake), then you will approach a more stoich mixture and make more power at the expense of additional heat. If the heat is enough to cause knock, the ECU will have to retard the timing to prevent full-on detonation, and thus lower the actual power created by the motor.
IMO, it just a lot easier to think of the fuel as being a necessary "catalyst" for the changing amount of air entering the motor. In tuning a turbo car, you just want to cram as much air in as you can, then make sure there's enough fuel to burn it all and keep things cool to prevent detonation, all while keeping from exceeding the overall pressure that the motor can physically handle.
BTW Dean, if you think Oxygen doesn't burn, you should talk the 24 people that "pretended" to die in this fire:
http://www.msnbc.msn.com/id/9449949/
Or ask Gus Grissom, Ed White, and Roger Chaffee that died on the Apollo 1 launch pad when a spark ignited their pure oxygen atmosphere.
http://history.nasa.gov/Apollo204/