Hello, I just bought a 66’ Belvedere with the original 225 L6 in it. The engine needs some work to it and I was wondering if I should just rebuild it or if I should swap it for another engine? And if I swap the engine out, what would be a good engine to put in it? Thanks for the help.

 

MM -

Rebuilding the 225 would be the easiest route, and you would keep the originality of the car.
Besides being less expensive, it might increase the valve, if all the numbers match.

A "bigger" motor would certainly be more fun, but you'd be looking at a transmission change (possibly), motor mounts, maybe K frame and suspension down the road.
A 360 crate motor might be the easiest route, but depending on your budget, the sky is the limit. Either way you will be opening a can or worms.

You really didn't give us enough info on the current condition of the car what you want on doing with it.

Archer