Found some more info on your question OP
http://www.sr20forum.com/sr20ve-sr16ve/ ... eable.html
SR20's have two intake manifold designs, high port and low port, and within those two designs, only some are interchangeable due to the positioning of the bolts.
So in short, if you have a 91-93 sr20de and wanted a det intake manifold, look for one off of an awd sr20det. You want a high port manifold.
But if you have a 94+ DE, you might have to look for a SR20VE mani as this is the only one that will almost bolt up to 94+ SR20's. The guy mentions he is not sure if it bolts up 100% correctly. These are low port manifolds.