Like the oil pan, this engine's headers involved hours of careful fabrication (by Paul Swindelhurst of McLaren's fabrication shop). The tuned, equal-length design was based both on the headers' fit in the car and the approximate horsepower of the engine. Even the cylinder heads' flow was factored into the design and tubing diameter. Also, they were designed for easy spark plug access. The 23-inch-long headers boast 2-inch primaries and 3.5-inch merge collectors.