Rich, Tug,
After I read Tugs thread a month ago and looking at his pics, I noticed that the distributor was dropped in rather awkwardly.
Last year, I was having problems with my computer system on my '81 and decided that I might rid myself of it if I could'nt troubleshoot the problem. I went out and got myself an earlier
non-EST/HEI distributor and an earlier non-TPS Q-jet. I rebuilt both to new conditions. However, I was able to troubleshoot and fix my computer problem. I kept the earlier units thinking that someday I might run an experiment with them.
Tug, after reading your thread a month ago I was inspired and tried the modification. These were my findings:
Some Earlier pre-1981 V-6's did not come with an air pump. HEI distributors that came on these V-6's were vacuum controled. Thus, the bracket assembly that holds the later air pump would obstruct an HEI distributor's diapragm resulting in limited adjustment, (if any), on the timing. That is why the air pump and assembly on Tugs 83 is missing, (or removed altogether).
Even with this though, the earlier HEI distributor cap and no. 1 plug is not in the same place as the later '81 and up EST distributors. This would mean that the possibility that the distributor was dropped in the wrong place is evident in Tug's 83. One must know how to modify this properly. On my experiment I had to file a new notch on the earlier distributor and I used the later '81 distributor cap so that it would fall in the exact place as was meant to be on the later V-6's. I got everthing running smoothly and perfectly tuned. But my final thought on this experiment was that the EST/HEI distributor system was vastly superior to the earlier vacuum controled type HEI distributor. It responds smoother and faster then the vacuum/HEI's.
Tug, if you still have the wiring and computer on your '83 only that it was disconnected and not butchered. Then get yourself the later EST/HEI distributor, later TPS control carburetor, and install the coolant sensor on the intake. (And hopefully the oxygen sensor is still attached on the exhaust manifold).You will never get that V-6 to run properly without it. Reverting that V-6 correctly to an earlier system is time consuming and very much involved.