These black PHBH carburettors have a pull choke instead of a flap choke. We use a 350 float needle valve in conjunction with a 50 throttle slide. The intake funnel with a 62mm connection width is perfect for large air filters as well as the connection of the original intake hose. The PHBH carburettors from SIP Performance have a basic tuning that provides a solid starting point for finding the right setup. However, the fine-tuning to match the corresponding engine setup must be carried out in each case by yourself and in each case engine-specific!