Originally Posted by
THEFERMANATOR
For the trans, it goes 91-93, then 94+ as far as controls go. Yes the harness changed mid year 93, but the pcs and valve body did not change until 94. So use the correct programming for your trans as 91-93 requires a "cleaning cycle" every 10 seconds to keep the pcs clean and functioning. Every 10 seconds it goes max line pressure to stroke the pcs to clean it. There is an accumulator/buffer circuit built into 91-93 valve bodies to slow line pressure response so the cleaning cycle doesn't damage anything.
Also of note, all v-6's, small block's, and big block's to 93 ran low pressure injection(8-13 psi), but 94/95 454's ran high pressure tbi(32-38 psi) injection, and the stock injectors in a 95 are actually some of the smallest used, but compensated with higher fuel pressure. So make sure which injectors you're using and use the correct fuel pump capable of supplying the needed pressure(most run the 96/97 vortec pump for overkill, or a tpi pump). Tbi pumps are lucky to hold 13 psi from my experience, 94/95 454's had a different pump(40 psi), tpi's another(50 psi), and 96/97 vortec's used the highest pressure pump(65 psi). Running the wrong combo can lead to some NASTY hiccup's and extreme lean out.