Threaded Metal Inserts for Plastic Intake Manifolds
#34164 from Kent Carter · Rule change · TB 23-06 (2023-06 Fastrack)
In B-Spec and C-Spec Categories Specifications, GCR Section 9.1.10.E., add the following:
"48. All cars which use throttle body to intake fasteners directly into a plastic intake, are allowed to convert the intakes to
accommodate a metal threaded insert. This is done for the sole reason that repeated removal of the restrictor plate wears the
threads in the intake and eventually causes the need to replace the intake."