Allison mt643 help
Hello, I am wondering what the function of this airline is on my 1995 allison mt643. I've been told by others it's a vacuum sensor hose and that these transmissions decide when to shift based on the rpms of the engine. This makes sense as before I cut this line it went to a tee/junction. The other hose coming from this junction went to the accelerator. Here is my issue though, I am putting this transmission into a bus with hydraulic brakes and no longer have the cummins air compressor as I removed it to make room for the gear driven vacuum pump I need for said hydraulic brakes. I am concerned about the transmission shifting correctly and am looking for advice.
This engine/tranny was a rear engine setup out of a 1995 bluebird, now a front engine setup in a 53 chevy.