OK Guys, I need some expert help... I am in the process of replacing the trans in my 70 Mav. I am replacing the factory 70 trans with a C4 out of a 73 Mav. My question involves the shift diaphragm modulator. The 70 C4 had the screw in single hose style. The 73 C4 came with the dual hose push in type that is held in with a bracket. I bought a new single hose push in type from AutoZone, but the bracket from the dual hose mod doesn't fit. Question #1: What mod and/or bracket do I need to use to make the single hose style work on the 73 C4 trans? Question #2: Do I need to use the dual hose mod, and if so, where does the second vacuum line feed of off? Sorry for the long explanation. Any help or advice would be GREATLY appreciated.
You have a PM! so anyone else can reference this in the future here is what you do: Use a "green stripe" modulator (single line out the back). cut the opening in the holding bracket wider to fit the hose. Install the modulator first then put the clamp in place. If you must use the two line modulator then only use the rear hose connected directly to manifold vacuum. (the green stripe modulator gives better over-all performance) (the second line normally goes to the EGR system vacuum and can be eliminated and plugged at the valve) Do not plug the second modulator connection - it will disable the modulator and you will have erratic and soft shifts.
