Accurate AFR data is critical when tuning an engine. Running rich (very low airfuel ratio, excessive fuel) can cause a loss in power, while running too lean (very high airfuel ratio, not enough fuel) may result in serious engine damage. Using a wideband airfuel controller during the tuning process allows you to monitor AFR and adjust tuning parameters to optimize them for maximum power and efficiency. AEM has a comprehensive line of highly accurate, reliable wideband airfuel controllers that can help ensure your vehicle is optimally tuned.