I have Halon in my 986 mounted to the front of the passenger seat, I always figured I would spray it through the side intake vents and hope the Halon does it's job in the enclosed space of the engine bay. If I tracked the car regularly a fire suppression system would probably be a good idea. That said, I don't think engine fires are all that common. The video above was someone that retrofitted an Audi V6 turbocharged engine, I think I have only heard of one stock 986 catching on fire.
These are Porsche's not Ferrari's, catching on fire is less of a concern.
