not always firing on #1

[Chryco Psycho]

If you rock the plactic fitting in the booster it should be holding vacuum even a day later as the fitting is a check valve or you can also use a vacuum pump or just suck on the hose to the booster & see if it holds .
Just plugging the port in the intake may change the way the engine runs 

[Strawdawg]

  The way its misfiring sounds like plug wire interchanged at the cap.

I have been wondering about this since an earlier comment about the firing order

[john h]

I have been wondering about this since an earlier comment about the firing order

I will check it again, but I traced the wires to the proper place in the cap a number of times.  It never hurts to check again.  I have it wired like a traditional '73' small block.  it's the 5.9 L magnum motor with fuel injection that is different.  I have the standard ignition system to the 73 era car.

[Strawdawg]

It is easy enuf to look up the firing order for that engine so I would guess the odds are in your favor! 

The other thing that is suspicious is the bad running that happened when you set the air gap on the pick up to the right number.  That makes me think the distributor is worn out at the upper shaft bushing and it is wobbling.  that is the only thing that I can think of that would cause that problem.  It should run considerably better with the 0.008" gap.

[john h]

Update.  Another day a fresh start.  The issue has been mostly fixed!  It surges a little bit at 40 or so, but 50 is great. start to any speed is great.  just holding at 40 has a surge. it idols great, the miss is gone! Both sides of theexhause sound good.  I can tune it withe the screws and see a change in lean rich.  That has been a long time since that has been the case.  I'm not sure what the exact fix was, but I started over.  I put new cap and rotor on new plugs all the way around.(it was wired correctly)  I re grounded everything.  I pulled the carb and did new base gasket and I put teh jets needles seats etc in the jewlery cleaner.  I blew all the passages out of the carb.  it was very clean in htere to begin with, no green death because I run 93 octane premium no ethonal.  I did all that just to be sure.  I pulled the header off the driver side and got some header wrap,  wrapped it and used the insulator boots on the wires.  I"m not taking any chances. I also replaced 5 and 7 plugs and checked the rest.  SO anything or all could have helped.  I really appreciate all the suggestions guys.  It's great to have the car running on all 8 cylinders again.  what a difference it makes!

I'm going out to put some miles on
Thanks again-
John

[Strawdawg]

good news!  or as Neil would say, 

[tman]

Good to hear.  You did not mess around. 

[cudabob496]

OK, now undue everything one at a time, so we can figure out what it was?
Nevermind!