Well here is what I have done.

I was checking the timing the other day. Adjusted a little. Took it out for a drive. Couple of hard pulls through the gears.

Stored it for a week.

Fire it up and noticed it would not idle well. Seems I forgot the tighten the dizzy down. Flopping around.

I put it back where needed and adjusted the valves running. Everything seemed OK on the adjustment. One rocker did not seem to want to squish. Seems the resistance did not get tighter like the others, however I adjusted to a 1/2 turn. Cam is a hyd roller with roller rockers.

Took some disgreaser and spray off motor and oil. Did not blow off the water like I normally do. Was in a hurry to get somewhere. I let it idle for a couple of minutes and then shut the motor off.

Two days later I fired the motor and it would hardly idle below 1200. Took it out for a spin and seemed to have no power, popping through the exhaust on WOT runs.

Popped the dizzy to see if I had some moisture. Could not see any. Took ou the factory springs while I was at it and put some Crane blue and silver springs in (suppose to make the timing come in faster). Put some white lith. grease on the springs and buttoned it up.

Seems it will idle now at around 900 (this is where I normally let it idle). Took it out for a spin and and it still popped through the exhaust on WOT runs.

Timing is set at 18*/35*.

Motor sounds OK at idle, no odd noises that I can hear.

What am I missing here?

What have I done?

Thanks!

Boy, I'm begining to think a lobe is flat, I hope not. Maybe a dizzy problem?

My first response is... if it popping the timing is off or its running lean. Maybe the accelerator pump isn't shooting enough gas into the intake manifold on acceleration.

Well, maybe my timing light is off.

OK, here is a update.

Took the dizzy apart and did not see anything unusual. I did order a new harness and module for it.

Check carb, everything is good it appears.

So....I fired it up.

It idled on the fast idle. Once it comes did it does not want to idle below 1200. The motor you let it idle the better it will get. I did get it to idle at around 950 enough for a drive yesterday.

Timing is at 19*/36*, if my light is not off.

Car is better on the drive, but on a WOT run about 3500 it still starts breaking up and a occassional pop out the exhaust.

Anyone else have any idea?

I'm going to replace the module and its harness.

Really at lost here.

Don't know anything to do except maybe swap out some parts.

Maybe I should adjust the valves again?

What throws this one off is that you adjusted the timing before you had any problem with it. If your timing is correct I'd suspect the problem to be a weak coil.

I think I will borrow a light from someone to see if my light is off.

Sounds like the timing is retarded a few degrees, or sitting right around 0°. That'll cause both of your symptoms, not idling down good, and popping.

Well, finally found out what it is. Not good! Not good!! Broken valve spring. That is why the valve would never squish into the lifter.

Anybody running a hyd roller. Word of advice. DO NOT RUN ONLY A 1/4 TURN OF PRELOAD. I feel this may of lead to the breakage. I tried this when I was going to make a trip to the track. Did not ever get there!!!

Oh well, the money pit gets bigger. Looks like a good exhaust to build that 383!!!!!!!

check to see your distributor cap is secured on both sides.

Well, finally found out what it is. Not good! Not good!! Broken valve spring. That is why the valve would never squish into the lifter.

Anybody running a hyd roller. Word of advice. DO NOT RUN ONLY A 1/4 TURN OF PRELOAD. I feel this may of lead to the breakage. I tried this when I was going to make a trip to the track. Did not ever get there!!!

Oh well, the money pit gets bigger. Looks like a good exhaust to build that 383!!!!!!!
Broken valve spring will be easy to replace. See this thread:
http://www.chevelles.com/forums/showthread.php?t=144500

Dealer can get factory springs no problem. I replaced a broken spring on my BB last year. Had it done in about 90 minutes, only cause I wasn't familiar with how to do it. I now know how.

Good luck and let us know how it goes.