Neuspeed Unleashes the power hiding in your factory Engine Control Unit (ECU.) NEUSPEED engineers reprogram your ECU chip to increase turbo boost to approx. 1.1 bar (16.2 psi), optimize ignition timing under part throttle and full throttle load, and raise the rev-limiter and top speed governor. Horsepower is increased by approximately 25-30hp at the wheels. Denso IK22 spark plugs are recommended. CARB approved (D236-10) when used with a K&N filter or P-Flo, if available. For 2000-up Audi A4 1.8T throttle-by-wire engines. 91 octane or higher fuel must be used with this chip. Factory chip is soldered onto the printed circuit board, so your ECU must be reprogrammed at NEUSPEED's California headquarters. Upon placing your order, NEUSPEED will send you an ECU removal and pre-paid shipping kit. Once you remove your ECU and send it out via UPS, the total turnaround time is 3-4 working days.