uhh pretty sure there was a VG30DET.. just not in the USDM
I know it came in at least the Nissan CIMA's Stock....Maybe in some other cars as well...
anyway here are some pics/links
here is a link to a z31 with the VG30DET in it..
http://www.sugibuchi.com/Fairlady-Z/...t@z31_menu.php
here is a link to an s-13 coupe with a VG30DET
here is another lovely pic of the VG30DET