BBK'S CNC series line of long tube header systems is available in 1 5/8 and 1 3/4 sizes to support a large range of power levels. Top qualiy and made in the USA, BBK headers feature durable 3/8" header flanges. Both 1 5/8 and 1 3/4 versions end in a leak free 3" ball and socket collector flange to meet up to their required matching mid pipe. All BBK headers are pressure tested to ensure trouble-free performance. Full long tube systems will gains between 18 and 30+ horsepower depending on the application. Gaskets and hardware included.