I was able to measure the length, width and height of the Kato Cedric and Pulsar, and those dimensions multiplied by 150 are very close to the dimensions published on Wikipedia for the prototypes of these cars. So, the Kato Nissans are definitely 1:150 scale.
However, because the prototype Cedric and Pulsar automobiles were not imported into North America, no one is likely to notice that these models are oversize if placed with 1:160 scale vehicles on a North American themed layout. And while I have not figured out what North American cars these models could be used as stand-ins for, here are the dimension in 1:1 inches and 1:160 inches:
Cedric
Length = 1.2235 (actual inches) or 195.8 (1:160 inches)
Width = 0.4440 (actual inches) or 71.0 (1:160 inches)
Height = 0.3630 (actual inches) or 58.1 (1:160 inches)
Pulsar
Length = 1.0210 (actual inches) or 163.4 (1:160 inches)
Width = 0.4265 (actual inches) or 68.2 (1:160 inches)
Height = 0.3560 (actual inches) or 57.0 (1:160 inches)
The Kato Cedric's 1:160 dimensions are in the general range of many of the mid-size North American cars from the late 1970s through 1980s, and the Kato Pulsar's 1:160 dimensions are close to the early 1980s AMC Eagle Kammback, and somewhere in between the early 1980s Chevrolet Chevette and Citation.
Also, since Kato made the models to "fill" Japanese open autoracks, these cars could be low cost alternatives to fill North American partially enclosed autoracks where being able to determine the exact prototype of the vehicles being hauled is not critical. It will be interesting to see how creative N scale modelers will be incorporating these models on their layouts.

Edit: Here is a link to Kato's autorack model.
https://www.katomodels.com/product/n/ku5000