"The J's was the base model with a very basic interior, few standard amenities, and 14" steel wheels. The Q's model offered a slightly more refined experience and received electric options and an available LSD. The K's grade received the turbocharged SR20det in addition to the options offered on the Q's.

The rare Silvia A's "Almighty" was introduced in late 1992. Trim wise, the Almighty slotted between the J's and Q's, offering options not available on J's, but not including all the standard features of Q's. The Almighty was purportedly offered as a "purer" form of the sports car. The only available engine was the naturally-aspirated SR20de coupled with a 4-speed automatic transmission or 5-speed manual transmission."

Wiki.