727 shifting issues

[Gizmo327]

I currently have a 727 with reverse manual shift body connected to a B&M shifter. 

The issue I'm having is I take off in 1st gear and then shift the shifter to 2nd gear but feels like still in 1st then I shift to 3rd gear and it shifts and rpm's go down. Was thinking might even be that im starting in second when I select 1st gear, so I checked the shifter cable adjustment and it did not make any difference in the issue I'm having.

I'm hoping its something simple that I am missing and not a bigger problem

[Burdar]

The B&M shifter takes a special shift lever that has a different length then the factory one.  Put the shifter in 1st gear.  Then disconnect the shift cable from the lever.  Make sure the trans is actually all the way in 1st.  Do that with each gear.   

[RUNCHARGER]

Yup: Most aftermarket shifters don't work correctly with a Mopar and if it isn't working correctly it can damage the transmission.

[Chryco Psycho]

Cheetah is the only cable shift designed to work with Mopar shift spacing

[Gizmo327]

had recently did a filter and fluid change. Could that have caused an issue? Maybe something that might have jammed up the manual valve body?