* Different Engine Mounts: The 3.2L and 3.5L engines have different mounting points. You'll need to either modify existing mounts or fabricate new ones.
* Transmission Compatibility: While both engines might use the same transmission type (e.g., automatic), the bellhousing bolt pattern might differ, requiring an adapter plate or a transmission swap.
* Wiring Harness: The engine wiring harnesses are different. You'll likely need to extensively modify or replace the harness to accommodate the 3.5L engine's components. This includes sensors, injectors, and other electrical connections.
* Exhaust System: The exhaust manifolds and piping will likely not be compatible. A new exhaust system will likely be needed.
* Computer (ECU): The 3.5L engine requires its own ECU (Engine Control Unit) which is programmed specifically for that engine. You'll need the correct ECU and potentially a custom tune.
* Cooling System: The cooling system may need modifications to accommodate the 3.5L engine's different cooling requirements.
* Other Potential Issues: There might be other unforeseen challenges depending on the specific year and model of Intrepid. Things like accessory belt routing, power steering lines, and other components may need adjusting or replacing.
In short, while technically feasible, this swap is a significant undertaking requiring mechanical expertise, fabrication skills, and potentially specialized tools. It's not a project for a novice mechanic. You'll likely spend considerable time and money making it work correctly. Consider the cost of the parts, labor, and potential unforeseen complications before starting this project. It might be more economical to simply find a used Intrepid with the 3.5L engine you desire.
