SteedSpeed Manifold exhaust passages are TUBULAR inside!  (not a log style design)

SteedSpeed MSP Manifold is designed in CAD and machined on a Makino machining center.   Each manifold is machined out of 1018 steel and then finished with a thick ceramic coating that can stand up to 2,000 degrees. 

This manifold is designed to be bolt-on and a stock replacement manifold.  It includes the bung for the O2 sensor and a threaded port for the stock EGR pipe. 

The Mazdaspeed manifold design is intended to direct the exhaust at the turbo using the most direct tubular route possible.  This retains the kinetic energy in each exhaust pulse.  Each of the passages are fairly equal in length but for turbo applications, equal length is not important for making power on a turbo car.

The design and production method is protected by a US patent and made in North America.