Is it easy to replace a Chevy 350 with 427?

Replacing a Chevy 350 small-block with a Chevy 427 big-block is not easy, but the difficulty depends heavily on the specifics of the vehicles involved and the level of experience of the mechanic. It's a major undertaking, significantly more complex than swapping two small-blocks.

Here's why:

* Size Difference: The 427 is substantially larger and heavier than a 350. This means significant modifications to the engine bay might be necessary, potentially requiring extensive fabrication work. The hood may need to be raised or altered.

* Mounting: The 427 has different engine mounts and will require new mounts or significant modification to the existing ones to fit.

* Transmission: While some transmissions might be compatible, it's likely the transmission and associated components (driveshaft, etc.) will need modifications or replacement to handle the increased torque of the 427.

* Exhaust System: The exhaust system will require a complete replacement.

* Wiring Harness: The wiring harness may need modifications or replacement to accommodate the 427's electrical components.

* Cooling System: The 427 will generate significantly more heat, requiring a more robust cooling system (radiator, water pump, hoses).

* Fuel System: The fuel system may need upgrades to provide adequate fuel for the larger engine.

* Accessories: Alternator, power steering pump, and other accessories might require changes or relocation.

In short, while mechanically possible, swapping a 350 for a 427 is a project best undertaken by experienced mechanics with access to specialized tools and fabrication equipment. It's not a weekend job and will likely require considerable time, effort, and expense. Unless you have significant mechanical experience and expertise, it's highly recommended to have a professional perform this engine swap.