I disagree on the comment on the new Nissan's, the changes to the new Nissan are not simply cosmetic and shape. This new engine has significant improvements, they changed the routing of the coolant flow to create a more even temperature dispersion, the water pump and fan blades have been modified to increase coolant and air flow. This engine through managing heat, has provided some astoundingly low emissions, and fuel consumption while increasing performance substantialy.
If you don't believe me, try a fuel consumption test, it will blow your mind.