I’m aware that EU-spec cars are equipped with gas particulate filters (GPF/OPF) which mute sound compared to cars exported to the States and Canada. Does anyone know if Japan-spec 992s have this OPF?
Secondly, does the filter affect performance/top-end acceleration at all?
Opf delete is a popular mod to increase power and/or sound. Not sure if the efficacy, though. My race shop says most power is gotten from the header mods.