[truegearhead]

NASA guy here. I run TT5 (same rules as ST5 and St-3 with less power). I don’t see anything not allowing swan necks and I know I’ve seen them. I only see the two limitations below in reference to wing design and rear bumber modification. I’ve also removed my rear bumber bar and cut my rear bumper cover and it passes tech. I also run a huge wing with 255s all around (which are also legal in ST3). The wing and splitter knocked off almost 2 seconds off my LapTimer at VIR. Right now it’s a spec boxster + aero and consistently runs time faster than the spec boxster lap record so that’s proof enough to me that the aero is worth it.


) Single rear wing or spoiler that does not exceed a height of 8” above the roof line, or width greater than the vehicle’s body width, or end plates greater than 12” in length or height, or 12” protrusion from the rear of the vehicle. Body width does not include flared fenders, mirrors, splitter, door handles.

Cutting/removal of the rear bumper cover/fascia where it does not cover the rear frame/bumper cross beam.