Strange problem, Pertronix maybe? Options

[Coy]

Okay I have a 74 2.0 with Hydraulic lifters. I’m running a 050 distributor with a Pertronix electronic ignition and dual Webbers. It’s been running well for about 7 years with this setup. I put new Triad exhaust on it earlier this year and it's kind of loud. (IMG:style_emoticons/default/biggrin.gif)

Earlier this year it started backfiring and popping and it sounded like maybe I had a collapsed lifter. Ends up I had two partially collapsed lifters but now I’m wondering if that really had anything to do with this problem. Anyhow, I got it all fixed and timed and it seemed good… smooth idle at 1200 RPMs with lots of get up and go for a 4 cylinder. I'm the happiest man in the world!

Then all the sudden the next day, it’s running crappy again; idling at about 800 RPMs and popping every once in awhile through the carbs going down the road. It pops every once in awhile through the exaust too... but maybe it's just feedback from the Triad exhaust, I'm not really used to it yet.

I thought maybe I might have some water in my gas, so I tried some Gumout fuel drier. I took it for about a 30 mile drive and when I got to the next town it was idling smooth at about 1200 RPMs no more backfiring. I'm the happiest man in the world again!

Stopped to top off the gas and when I went to shut it off it over ran like the timing was off. Started it right up and it was idling at about 300 RPMs and kind of shuttering, but it still seems to smooth out on the freeway.

Drove home to intermittent popping and farting and idling at about 800 RPMs before I put it in the garage and shut it off. Messed with it a bit, but it was idling smooth again and reved smoothly.

Next day I drove it about 80 miles. I stopped about 3-4 times and it was idling somewhere up and down between 300 and 1200 RPMs every time I shut it off and restarted it. It occasionally backfires, but still runs really great out on the highway.

Any guesses based on that description? Has anyone else had similar experience with Pertronix? I’ve heard that they can both 1) slowly shit-out on you or that they can 2) just stop working and leave you stranded on the side of the road all of a sudden.

The distributor seems tight and the rotor snaps back when I test it, so I think it’s good. Is there any way to test the Pertronix besides just buying a new one?

I didn’t install this electronic ignition, so I’m not even sure how it works. The backing plate still looks to be in tact; can I just get a set of points and condenser and test the distributor itself to see if it’s going bad all by itself?

Does anyone think this sounds like carb trouble?

Your collective genius is greatly appreciated.