Ok I think I figured out what you are saying, you want to convert a long shaft c6 to a short shaft c6. To remove the tailshaft I think just about the entire trans has to come apart. And make double sure your bellhousings match. If you have a diesel sell that car trans and rebuild yours.
Remove your kickdown rod (with the vrv it isn't needed mines been off for 3 years) and tip the vrv on the side of the injection pump a little at a time until you are satisfied. The VRV should need to tilt towards the front of the truck.
Have 85 f250 4wd 6.9,putt 4'' lift on it other day now trans,shudders when taking off and feels like im pulling heavy load trans was rebuilt maybe 5000 miles ago,fluid looks good,has always shifted hard, thoughts?
Mine is '83 F250 6.9. I too have developed the shift into/outof 3rd at 45mph problem.
After reading the first page of this I checked and found:
My pump is maintaining 20+ Hg.
The top port of the VRV holds 0 Hg. So I guess it's hosed.
I have broken one of the VRV adjustment clamping screws and can't get the other to budge. Steel screw in white metal and apparently no anti-seize. Have PB Blaster-ed it a few times over the last few of months. I guess I could go ahead and put some heat on it to break the screw loose and not worry abut melting the VRV if I am going to replace it anyhow,
Is there other plastic that could be damaged back in there?
Also - I had an idea and just connected the vacuum supply to the trans modulator line and I get good shifting!
Why does this work?
Will the 20 Hg ruin the modulator?