* Displacement: While numerically close, the actual displacements differ. The 289 is slightly larger. This isn't a huge difference but contributes to other variations.
* Design: The 289 is a small-block pushrod V8 – a classic design with pushrods actuating the valves. The 4.6L is a modular aluminum V8 with overhead camshafts (OHC), a much more modern design. This is the biggest difference.
* Materials: The 289 uses a cast iron block and heads. The 4.6L uses an aluminum block and heads, resulting in a significantly lighter engine.
* Technology: The 1994 4.6L benefits from nearly 30 years of advancements in engine technology. This includes things like:
* Electronic Fuel Injection (EFI): The 4.6L uses EFI for precise fuel delivery, whereas the 289 likely used a carburetor (though some late-model 289s might have had early fuel injection).
* Computer Control: The 4.6L's engine management system is computer-controlled, optimizing performance and emissions. The 289's control is far simpler, relying on the carburetor and basic mechanical components.
* Camshaft Design: OHC design in the 4.6L allows for more advanced cam profiles and better valve control.
* Cylinder Head Design: The 4.6L's heads are far more sophisticated, with better flow characteristics and more efficient combustion chambers.
* Power and Torque: While specific outputs vary based on application (e.g., Mustang vs. other vehicles), the 4.6L generally produces more power and torque *per liter* than the 289, thanks to its modern design and fuel injection. However, highly modified 289s can certainly outperform a stock 4.6L.
* Maintenance: The 4.6L, with its more complex electronic systems, likely requires more specialized tools and knowledge for maintenance and repair than the simpler 289.
In short: comparing a 1964 289 and a 1994 4.6L is like comparing a horse-drawn carriage to a modern sports car. They both get you from point A to point B, but the technology, performance, and maintenance requirements are vastly different.
