* Different engine mounts: The 3.5L and 2.7L engines have different physical dimensions and mounting points. The 1993 3.5L engine will not simply bolt into the 2000 Intrepid's engine bay. You'd need custom engine mounts fabricated.
* Different transmission: The transmissions compatible with the 2.7L and 3.5L engines are different. You'll likely need to swap the transmission as well, which introduces further complexities. Finding a compatible transmission from a 1993 vehicle might be difficult.
* Wiring harness incompatibility: The wiring harnesses for the two engines are entirely different. You'll need to extensively modify or completely replace the wiring harness, which is a major undertaking requiring detailed electrical knowledge.
* Computer/ECU incompatibility: The engine control unit (ECU) from the 1993 3.5L will not work with the 2000 Intrepid's systems. You'll likely need a standalone engine management system, adding significant cost and complexity.
* Exhaust system incompatibility: The exhaust manifolds and systems are different and will need to be replaced or adapted.
* Cooling system incompatibility: Radiators, hoses, and other cooling components are likely incompatible.
In short, while theoretically possible, this swap is a massive undertaking requiring advanced mechanical and electrical skills, custom fabrication, and considerable time and expense. It's far beyond a simple engine swap. It would be far simpler and more cost-effective to find a replacement 2.7L engine or even consider a different engine swap with a more compatible model.
