Here's why:
* Bore Size: The 305 has a smaller bore (3.736") than the 350 (4"). This difference in bore diameter results in a different rod length to maintain proper piston and crankshaft alignment.
* Rod Length: 305 connecting rods are typically 5.7" long, while 350 connecting rods are 5.7" or 6" long. The 6" rods are often found in later model 350s and are stronger and more desirable for performance builds.
It's important to note that even within the same engine family (e.g., small block Chevy), there can be variations in connecting rod lengths and other specifications depending on the year of manufacture and specific engine model.
If you're planning to swap parts between a 305 and 350, always double-check the specifications to ensure compatibility and avoid potential problems.
