V6 engines come in different cylinder bank angles. The angle which is most efficient among them is 60 degree. It helps in minimizing the size and vibrations. Flat-6 and inline-6 engines have more balance than a 60° V6 engine.
But, the latest techniques in mounting and designing have greatly disguised the vibrations produced in them. 60 degree V6s do not require balance shafts for making them smooth in operation. The modern designs generally make use of 3-throw crankshaft.
This helps in providing the desired 120° separation and can also help in the balancing purposes. The ends of crankshaft contain heavy counterweights pair for eliminating most of the secondary imbalance.
This configuration proves useful for cars that are comparatively larger and where four-cylinder engines do not prove sufficient. It is useful where low cost and compactness are required. General Motors built 60° V6s that has become very popular now.