Yaris Intake Manifold

[dallas]

With previous dyno runs with bigger intake manifolds and throttle bodys without more displaement, more cam, or forced induction a higher flowing intake will offer very little gain and may loose h.p /torque until very high rpm.
What calculations are you using for runner diameter and length.

[richardholdener]

Is this question directed at me? The statement that a higher flowing intake will yield very little gain and may loose hp until high rpm is inaccurate. Intake manifolds are not simple flow devices-they are tuned to produce power at specific engine speeds based on the other variables you mentioned (displacement, cam timing etc...) It does not take a bigger or higher flowing intake to make more power, it takes the right design elements. The calculations are extremely complicated for more reasons than I can go into in such a short space. We ran over 100 different combinations before deciding on this one illustrated by the dyno curve provided. Intake design is more than just welding together a plenum, runners and flange.

Originally Posted by dallas

With previous dyno runs with bigger intake manifolds and throttle bodys without more displaement, more cam, or forced induction a higher flowing intake will offer very little gain and may loose h.p /torque until very high rpm.
What calculations are you using for runner diameter and length.

[richardholdener]

PS-The tuning effect works the same on NA and FI applications.

Originally Posted by dallas

With previous dyno runs with bigger intake manifolds and throttle bodys without more displaement, more cam, or forced induction a higher flowing intake will offer very little gain and may loose h.p /torque until very high rpm.
What calculations are you using for runner diameter and length.