I want to replace my 93 intake with a 94 up intake and fuel rail set up, is there anything else that I will need to replace except the fuel line extensions? Also can a 95 and up timing cover work on a 93 if I switch to the vented opti and longer pin cam?

 

Why do you want to change the fuel rails? The 93 has batch-fire injectors, not sequential like the 94 and ups. The 93 rails were designed for batch fire.

The is no "95 and up" timing cover. There is a 95 with the larger hole to allow the cam dowel to drive the Opti, and 96/97 with the larger hole and the mount for the CKP sensor. If you do a complete vented Opti swap - cam, timing set, vented Opti, vacuum harness and electric harness, you can us a 95 or a 96/97 cover. You would have to plug the cam sensor hole on the 96/97 cover.