Gizmo's Racing modified Walbro WT-1048 carburetor is bored and the mouth of the carb has a radius inlet to allow a smooth and even entry of air into the intake duct with the flow stream adhering to the carb walls. The flow-contoured entry is designed to reduce boundary layer disturbance as high velocity air enters the intake path. Results include improved air stability and increased engine performance. **The carburetor also comes with the needle clamp** NOTE: THESE ARE PORTED ON A CNC MACHINE SO WE CAN GET PRECISE BORE SIZE EVERY TIME. All our Carburetors are Genuine OEM Walbro and not the copies that are being sold as OEM.