Does not fit with angel plug or raised port heads. Hooker Competition headers offer the best value in the high performance header market. Designed for the value-conscious buyer who is running either a stock or mildly-modified engine, Hooker Competition headers offer premium features at a very competitive price. Made of durable 16 gauge mild steel tubing, the Hooker Competition header design utilizes a long transition collector to reduce back pressure and increase exhaust flow. A perfect sealing surface is assured with the 5/16 in. machined flanges, with welded O-ring seals. Experience has proven that this flange size is ideal to maintain header integrity and be pliable enough to seal each exhaust port. Tubing is mandrel-bent to maintain metal strength and provide consistent tube diameter at radii to maximize performance.