What is a true individual runner manifold?
A true IR manifold is one where the individual throats are completely segregated from the adjacent throats, allowing the highest possible air speed, for not only maximum efficiency, but also low speed drivability. It is fashionable today for other IR manifold manufacturers to incorporate a common plenum, making them a hybrid design, muting the advantages of an IR manifold (maximum power and torque, engine acceleration rate, and especially low speed drivability associated with our tremendous cylinder fill) while at the same time, introducing the disadvantages of a common plenum manifold. The primary reason for this hybrid design is for the use of an IAC valve. Since it is not feasible to build the plenum large enough to not be affected by the operation of the IAC, a reduction in resolution for the MAP sensor, along with noticable decrease in low speed drivability, is experienced. A second reason for the hybrid style intake is, it is thought to eliminate the need to correctly synchronize the butterflies. Unfortunately, this is not the case as butterfly synchronization is also required for the hybrid designs.