Mustang PI Intake Manifold Swap Overview

What is it that changes when upgrading from the 1996-1998 NPI heads and intake to the 1999-2004 Mustang GT’s PI heads and intake that makes the swap so complicated? The NPI heads that came stock on all 96-98 GT’s use a different internal design therefore creating the need for a new intake manifold. When you are upgrading your intake and your heads you’ll also need to pick up some additional parts depending on your year.

New Hoses: The difference in design causes issues with hose and bracket location’s on 1996-2000’s. The new intake manifold has a longer aluminum reinforced runner that extends the hook up to the thermostat housing. This requires the need for a new hose kit like that on the 99-04 GT.

New Brackets: If you own a 96-00, you will also need a new alternator bracket from 01-04 GT to relocate it. This bracket makes install easy allowing all your hoses to fit properly and relocates the alternator for proper thermostat fitment.

What about PI Heads? The 99-04 GT came stock with this higher compression, cooler running PI head. The 01-04 GT also came stock with the aluminum reinforced intake manifold and together they produce nearly 40 more HP compared to NPI set ups.