If you'd like some more information about what is going on in the engine, the Vems wideband is the 2-in-1 gauge which offers you a wideband afr and exhaust temperature in an unbeaten 299€ price of 299€ - sensors & wireing included.
K&N products still on promotion for a while!
The K&N Air filters are on promotion for an other few days. The -10% discount will end at March 5th. This is a good chance to ease the breathing of the engine for a competitive price.
Read more about the promotion here: K&N Promotion