Don't think there is a KA16DE. You might be thinking of a KA24DE, which comes stock in the 240sx/Altima, or the KA24E which came stock in the King Cab.
Here's some info on the KA24E:
KA24E
Here's some info on the KA24DE (towards the bottom of the page):
KA24DE
Here's a bit more on the KA24DE:
More on KA24DE
What do you need to know about these engines? The difference between the 2 is that the KA24E is a SOHC engine, whereas the KA24DE is a DOHC engine. The KA24DE is more powerful.