Integrated tuned induction system

In an induction air circuit for a multi-cylinder internal combustion engine the combination comprising a plenum zone that is supplied with air from an air intake, and spiral runners leading from said plenum zone and through which air is supplied from said plenum zone to individual cylinders, said runners laterally bounding said plenum zone at locations along the length of said plenum zone, at least one of said runners having an air entrance at said plenum zone and spiraling from said air entrance in excess of 360 degrees about a longitudinal axis of said plenum zone to an air exit through which air passes to an engine cylinder, a first segment of said at least one runner and a second segment of said at least one runner which is disposed at least 360 degrees about said axis from said first segment sharing a common wall portion, and wherein said plenum zone and runners are embodied in a single plastic part.

In an induction air circuit for a multi-cylinder internal combustion engine the combination comprising a plenum zone that is supplied with air from an air intake, and spiral runners leading from said plenum zone and through which air is supplied from said plenum zone to individual cylinders, said runners laterally bounding said plenum zone at locations along the length of said plenum zone, at least two of said runners being arranged as to a nested set in which they share a common wall portion extending along at least portions of their respective lengths, said nested set having air entrance means at said plenum zone and spiraling therefrom in excess of 360 degrees about a longitudinal axis of said plenum zone to air exit means through which air exits the runners of said nested set, said nested set comprising a first segment and a second segment, said second segment being disposed at least 360 degrees about said axis from said first segment, said first and second segments sharing a further common wall portion other than said first-mentioned common wall portion, and wherein said plenum zone and runners are embodied in a single plastic part.

In an induction air circuit for a multi-cylinder internal combustion engine the combustion comprising a plenum zone that is supplied with air from an air intake, and spiral runners leading from said plenum zone and through which air is supplied from said plenum zone to individual engine cylinders, said runners laterally bounding said plenum zone at locations along the length of said plenum zone, and at least one of said runners, when viewed in transverse cross section through said plenum zone, having a beginning at a given circumferential location about a longitudinal axis of said plenum zone and spiraling from said beginning in excess of 360 degrees about said longitudinal axis of said plenum zone to terminate at an ending that is in excess of 360 degrees about said longitudinal axis of said plenum zone as measured along the length of said at least one runner, wherein said at least one runner and another runner share a common wall portion along at least portions of their respective lengths, said plenum zone and runners are a single plastic part, and a first segment of said at least one runner shares a common wall portion with a second segment thereof which is disposed at least 360 degrees from said first segment as measured about said longitudinal axis of said plenum zone.

In an induction air circuit for a multi-cylinder internal combustion engine the combination comprising a plenum zone that is supplied with air from an air intake, and spiral runners leading from said plenum zone and through which air is supplied from plenum zone to individual engine cylinders, said runners laterally bounding said plenum zone at locations along the length of said plenum zone, and each of at least certain ones of said runners, when viewed in transverse cross section through said plenum zone, having a beginning at a given circumferential location about a longitudinal axis of said plenum zone and spiraling from said beginning about said longitudinal axis of said plenum zone to terminate at an ending that is disposed a certain number of degrees about said longitudinal axis of said plenum zone as measured along the runner's length, wherein said plenum zone and runners are a single plastic part and wherein segments of said at least certain ones of said runners are immediately contiguous along the direction of said axis, each immediately contiguous pair of such segments sharing a common wall portion that separates the segments of such pair along the direction of said axis.