Here's why:
* Engine Strength: The 1998 Taurus V6 wasn't designed for forced induction. The internals (pistons, connecting rods, crankshaft) aren't as robust as those in engines built for turbocharging. Higher boost pressures from the turbo will likely lead to premature engine wear and failure unless significant internal upgrades are made (forged internals, etc.).
* Fuel System: The stock fuel system isn't designed to handle the increased fuel demands of a turbocharger. You'll need upgraded fuel injectors, a fuel pump capable of higher flow, and likely a fuel management system (e.g., adjustable fuel pressure regulator, aftermarket ECU) to provide the proper air/fuel mixture under boost.
* Exhaust System: A free-flowing exhaust system is crucial for a turbocharged engine. The stock exhaust system will restrict exhaust flow and severely limit performance. A custom exhaust manifold, downpipe, and exhaust system will be required.
* Intake System: An upgraded intake system is also needed to deliver sufficient airflow to the turbocharger.
* Cooling System: Increased heat is a major issue with turbocharged engines. The stock cooling system will likely struggle to keep up, requiring upgrades like a larger radiator, upgraded cooling fans, and possibly an intercooler.
* Transmission: The transmission may also require upgrades to handle the increased torque from the turbo.
* Tuning: Proper tuning is absolutely essential. An aftermarket ECU or piggyback system will be necessary to adjust fuel delivery, ignition timing, and other parameters to prevent damage to the engine and optimize performance. Incorrect tuning can lead to catastrophic engine failure.
In short, while technically feasible, turbocharging a 1998 Taurus V6 is a major undertaking that requires significant mechanical skills, specialized tools, and a considerable budget. It's far more cost-effective and less complex to purchase a car that already has a turbocharged engine.