It does help some thanks. I was able to get the car going again and avoid the richening problem when I open the throttle. Now it is idling and running okay, but it still dies if I play with the #2 lift pin. I've tried alternately richening and leaning out #1 and have kept both idles balanced with a unisync. The richness of #1 does not seem to be producing anything other than consistent death when I play with #2's lift pin. Weird.

Since it is running okay now, I'm not sure I want to fiddle with it much more but this weird behavior from #1 really bugs me. #1 is the only one of the two carbs to have the choke mechanism, so it is very important that it be doing it's job.

A couple of things could be contributing to my issue. First, the #1 carb was rebuilt with a later style SU23 kit that included an "improved" fuel jet with a straight pickup tube. The rear carb was rebuilt with an earlier style SU23R kit that had the more standard 90 degree elbow in the jet pickup.

Second, the fuel pump I have is a new "Volvo" pierburg fuel pump from "West Germany" (NOS?). Anyway, it puts out way too much fuel pressure which hits the forward carb first. I have an inline FPR but it's an off-the-shelf aftermarket device that has its own quirks.

I'm not sure of either of these two factors are really causing me trouble, but I wanted to ask for opinions.

Thanks