Join Date: Aug 2011
Location: Albuquerque, NM
Ferrari Life Posts: 11,856
Patrick- Removing the secondary air system will cause all kinds of problems resulting in check engine lights and other undetermined affects. Removing the primary cats, that everybody calls secondary, will not have much affect except on emissions. The 599 has precats in each of the 4 exhaust headers and that is where the emissions sensors are located, so no check engine light from removing the primary (secondary if you are selling bypass pipes) cats. Just pollutes the atmosphere.
The GTO actually went to only two exhaust headers with the primary cats in them and deleted that second set of cats. Those GTO cats, however, are larger and more efficient than the precats in the 599.
Present: 575M 135171
Past: Dino 246 GT 02984, 365 GTB/4 14009, 308 GTS 25125
Every day I look around, and if nobody is shooting at me, it is a pretty good day.