does anyone know the hp/torque specs for a stock e46 M3 w/ racing fuel as opposed to 91 octane?

I´m not sure if there are any official facts about that...

In germany the engine control unit of the m3 is optimized to run on 98 roz fuel. you won´t get any extra hp with 100 roz.

running a m3 on 91 roz may reduce it´s power of about 5-10% probably