Thanks to this site and all of you knowledgeable people. You have solved many of my questions before I even had to ask them.
I have a 72 510 that still has a stripped down L16 in it with dual Weber 42s. Yes, 42's are a bit large for an L16 and EI would be better than points. But I'm trying to work with what I've got for now. No emissions bs or anything else extraneous. Just the motor and trans. I did a full rebuild on the motor, swapped in a short tail 5 spd, and rebuilt the dual point distributor and both carbs. After a bit too much time guessing and tuning, I sprung for a wideband AEM gauge which made things much easier. I was able to get both the carbs and timing right, but I still had a high idle. 1350 rpm.
Okay, so this was a test thing to see what y'all thought about it. Since webers like a bit more timing than stock and also the old 42's (and 40's I think) don't provide for a vacuum advance, I had higher than normal initial timing. To solve this, I made creative use of my dual point distributor. I wired the second (retarded) point to a micro switch that only was on at throttle closed. This way, any time that the throttle is open, it runs off of the primary (advanced) point with an initial timing of about 14*. That's where the motor is happy up top at about 39*. I think that's a touch high, but no pinging or over heating occurs. Plugs and the O2 sensor look great 4000+. Idling on the primary point gave me an idle of about 1350 rpm. Not horrible, but not good. With the throttle closed, the switch activated, and the secondary point retarded 4* from the primary, it gives me an idle of 900ish. Much better. I was also able to re-tune for a bit more economy down low rpm.
I searched and searched but could not find any other threads about this specifically. I apologize if I did not see another post about it. If there is anything I am am doing wrong missing, let me know.
I have a few pics having trouble putting them in. I will figure it out and put them in later.
Ryan