Will struggle to start and driving will be virtually impossible.

Another good upgrade depending on what year your car is, is to swap the ecu for a 1999 spec. The early 1999 spec ecu AE801 has a much better fueling / boost mapping. The later 1999/2000 AE802 was mapped for better consumption and safety. Mine was a 2000 and had the AE802 and had a lot of flat spots in the rev range. Bought an AE801 and straight swap, and it was like a different car. More BHP too.