I need help to better understanding this engine situation. I have a 93 but I need to know which engines I can use? Can I use the 98+ vvti or non (2jz)? Please give me all the input you can.

 

WIth a 93 GS300 your car comes with a Non vvti 2jzge. In japan, your car also came with a non vvti 2jzgte from what they call a JZS147 Toyota Aristo. This isn't a plug n play swap but it comes close.

Swapping in a 98-2000 (vvti) into a 93 is much harder to do because of the wiring situation.