Can 350 chevey engine fit in 1966 cutlass?

A 1966 Oldsmobile Cutlass's engine bay is relatively spacious, but fitting a 350 Chevy small-block depends on several factors and isn't a direct bolt-in swap. You'll encounter significant challenges:

* Motor Mounts: The Chevy small-block and the Oldsmobile engines have completely different motor mount locations. You'll need custom motor mounts.

* Transmission: The transmission bellhousing bolt patterns are different. You'll need a Chevy-compatible transmission and possibly an adapter plate.

* Steering: The steering linkage and possibly the steering column may interfere with the engine's placement.

* Exhaust: The exhaust manifolds or headers will need to be custom-fabricated or adapted.

* Wiring: The wiring harness will be entirely incompatible. A custom harness will be required.

* Radiator: The radiator might need to be changed or modified to fit properly.

While it's *possible* with considerable fabrication and custom parts, it's not a straightforward swap. It requires a good level of mechanical expertise and access to fabrication tools. Many professionals would consider this a fairly involved project.