[SteveR]

Intake manifold and fuel rails were different in 93-94. Vented opti starting in 95, cooling system was a little different starting in 95. I've heard from a lot of people that the heads from 93 were a little better than the rest of them flow wise. Oh yea, the three versions were 93-94, 95, and 96-97. Timing cover was different on all three versions. If you start to build one from the ground up, just make sure the short block stays consistant year wise.