Integrated throttle body and intake manifold spacer module

An integrated throttle body and intake manifold spacer module for an internal combustion engine air intake comprising a throttle body having a through-bore extending along a longitudinal axis for conducting intake flow, a throttle mechanism comprising a blade disposed within the through-bore on a cylindrical shaft having an axis of turning substantially coincident with a diameter of the through-bore and journaled on opposite wall portions of the throttle body for turning about its own axis to selectively position the throttle blade within the through-bore over a range of positions spanning a closed throttle position closing the through-bore to flow and open positions;

• a torsion spring disposed about the shaft external to the through-bore for spring-biasing the throttle blade to closed position, the spring having tails at opposite ends, one tail being received in a slot formation in the exterior of the throttle body that is open toward a cam on the shaft exteriorly spaced from the throttle body, the cam containing a formation that locates the opposite spring tail on the cam such that the spring is torsioned between the cam and the throttle body to spring-bias the throttle blade, and in which the slot formation comprises a generally straight slot segment receiving a straight section of the one spring tail and a further semi-circular slot formation intersected approximately tangentially by the straight slot segment, and a semi-circular segment of the torsion spring being received in the semi-circular slot formation.