B Series Bisi Style Header V2 4-1 Merge Collector B18 B20

B-Series header features a true 4-1 merge collector for more equal exhaust flow.
This header delivers the best peak horsepower gains while utilizing a 2-piece design.
This is ideal for all forms of competition; Autocross, Drag racing and road racing.
Recommended for 1.8L - 2.0L engine displacements.
Made of 304 Brushed Stainless steel
True 2.65 (ID)inch collector outlet
Hand TIG Welded CNC-ed machined manifold flange
One year warranty 18G on the 304 S/S.
Measured at .049" to .050" OEM spec header gasket
OEM spec donut gasket
Two piece design Half core radiator must be used