c6 downshift rod theory and practice
I need an explanation of how the downshift rod works (or is supposed to work) on a C6 trans. The 351/C6 I got from the bone yard had the rod broken off at the transmission lever (actually looks like some fool did it on purpose). It could even have a piece missing because my '32 pickup also has a C6 and the lever is in an upside down "U" shape while the lever pieces I have for my boneyard tranny would basically make a straight line. However, they are from two different years so the levers might be different.
I need to either weld up the pieces I have or fabricate another lever. However, I need to know exactly how the rod is supposed to operate in order to fab up the lever correctly. I've never actually seen one of these operate because you obviously can't watch it in action when your going 50 and you hit the throttle.
Here's my theory from looking at my "good" (running) C6...so please correct what's wrong with it or add vital data.
1) At speed, when pressing the accelerator to WOT, the downshift rod is pushed downward (toward the ground).
2) This downward motion of the rod is transferred to the downshift lever which rotates the shifter in a counter clockwise direction (is this correct?) tripping the tranny into the next lower gear.
If this much of the theory is correct I think I can weld up the lever at the transmission correctly. (Actually, I've already tack welded it in a position which assumes the above is correct...so I might have to undo what I have if it's incorrect.) But then, how much play should I have at the carb when the engine is at idle, or should there be no play at all. Or said a little better...how do you adjust the downshift rod at the carb end to get the proper results. Also, short of doing a road test, is there any way to determine you have it set up properly once everything is welded and adjusted?