Over the past year or so I rebuilt a B20 and put it in my ’68 122. It’s bored out to .030 and has an Isky SP cam. Has SU carbs with a stock combination manifold.
I’ve been having some problems getting it to run smooth, or even close, really.
Since I first started it last week I’ve readjusted the valves at .020.
As I was starting to set up the timing I noticed that both the valves on #1 piston cannot be totally closed at the same time. Is that a characteristic of the cam, or a problem with the cam? Anyway I did my best to get it close and moved on. After I got the timing close I put the light on it. Couldn’t get it close to 10 BTDC so I boosted the idle up a little. It seemed to be OK at idle at 10 BTDC, but the car would do nothing under load and couldn’t even get out of the driveway. So I reset the timing at around 16 BTDC and was at least able to drive around the block. I turned it off. When I turned it back on it popped through the carbs, but started, barely. It loped untill finally dying. Started it again and gave it a little gas and it idled up. Turned it off and restarted. I had the timing light on it. While it was loping it read 0. After I just revved it a little it ran smooth at 16 TDC.
What does this strange pattern indicate? Cam and/or timing problems?
Trouble-shooting recommendations?