I have a 79 355 small block Chevy. It has an Edlebrock 1910 (850 CFM Q Jet), 9.5:1 compression, 268 degree cam with .454 lift and factory rocker arms. I run headers and flowmasters. I have been having problems with my engine running poorly and loading up at idle. It doesn't die, it just drops down to about 450 RPM and puffs a little fuel smoke. Today myself and 72 THING (Will) were putting in my Amsoil 2 stage foam air filter and setting the timing. We had trouble getting the timing light to work. After trying a different timing light, I vice gripped a spark plug to the power steering bracket and put the #1 wire on it with the truck running. The spark looked really weak and erratic. I put a Pertronix coil and HEI module on it less than a year ago. What could be causing this problem? I only had 11.79 volts and the distributer and the same at the battery. I realize this is low...I took my alternator back to the man who built it. I know low voltage at the battery is not the only problem because it did it with a brand new battery as well as with no alternator and a battery charger hooked up. Any ideas? Thanks in advance.