Interesting find here. I have four lower intake manifolds here:
1992 SSEi, salvaged by BillBoost and Pat
1993 SSEi, stock LIM on the Zilla, heavily modified :P
1995 SLE, stock LIM on the SLEeper
1995 ???, salvaged by LakevilleSSEi
The 92 looks just like my 93. The 95 Nate sent me has a crack running down the 'hump' on the inside of the LIM. This is very likely why the LIM was horrible inside. Coolant leak. Probably also why the ignorant former owner removed one of the ECT sensors and installed a plug.
They never knew they were overheating.
Aside from that, there are some REMARKABLE differences between the 92/93 and the 95. However, all the older part numbers have been obsoleted, so it wasn't a MODEL change, but rather a part improvement that obsoleted previous units.
LIMs are marked as such:
1992 SSEi, 24501562
1993 SSEi, 24502104
1995 SLE, 24502302
1995 ???, 24502302
24502302 is the only valid current part number.
So what'* the difference between the 92 and 93?
I've seen the differences between the 92 and 93 and the 95. Very obvious, and I'll post pics later.
This is just a precursor to more investigation, but this may answer some more questions as to why the performance between the 92 and 93 is so different, as well as the 94/95. Keep in mind the larger throttle body and more efficient blower came on the 94/95, but with a smaller pulley. But now it looks like the last LIM change came in time for 95 production.
Further LIM development work is on hold until I know what the differences are and how they will affect performance. Particularly the 95 LIM.