I know the MAP sensor provides a signal to the ECM based on the manifold vacuum, but what does the signal actually affect in the computer? Although it appears that on the outside all GM MAP sensors for TBIs and electronic carbs are similar, the connectors from vehicle to vehicle are different; that is the plastic protective barrels that slip into the socket have the grooves cut in different places. Also if they were exactly the same, why do they all have different part numbers from application to application (and different prices, too)? I'm going through all this because I'm wondering if the MAP for my original 305 is sending the correct information to the computer to run the 350HO I now have powering the car or if I would see a difference if I got a MAP for a Vortec 350 powered truck/SUV.
Thanks for your comments.

 

The MAP is used in all your computations involving load.
Timing, fuel, PE etc.
There are several families of sensors that appear about the same but in fact are different, ie 1-2-3 bar MAP sensors, and baro sensors all look the same but the connectors are different.

A 1 bar MAP is a 1 bar MAP. So no there is no difference other then possibly the difference in tolerances.