I have a 383 w/ 727 trans. trans is rebuilt, but sat for a while. Shifts into gear good, but I have a problem. I tried to test drive today. wont shift out of 1st...What might it be? It has a new cable kick down.

Ideas???? Need help. Might it be band adjustments?

I have only drove it 2 trips that were only 1/2 block each way. It was revving high and holding its gear. My buddy just told me to go put a mile on it, then see???

I had this problem with a 727 in my Charger years ago. I had a 727 rebuilt to swap in, then some time passed. 18 months later I swapped headers and installed the "rebuilt" trans, along with a 3000 stall converter. It seemed okay at first, but within a couple of miles the trans seemed to slip alot. At one point while in park, I couldnt rev it past 2800-3000 rpms and it felt like it was both in gear and in park at the same time. When I smelled the fluid, it was almost black and really stunk.
The shop covered the trans. Sure, I had to swap it out, but no BFD. Later when they tore the trans down, the man said that the clutched were welded to the case and grit was everywhere inside. The trans was scrap. NOT trying to scare you, but I have wondered for awhile if the trans was AFU from the start or did it cause damage sitting through the summer and winter....Hmmmmm.

I'll echo the rest..adjust your cable, better yet get rid of it and get the right linkage.

Found out that it has a reverse valve body. The tranny was rebuilt by a local mopar performance shop. It was a left over they had. I guess they forgot to fill me in. Should I leave it in or change it? And does that mean my kick down is not usefull now?

I'd leave it in. You'll just have to shift it manually. and No you shouldn't need the kickdown. But ask the trans shop.