Odd "miss and hit" during acceleration

[Argess]

I guess there is no way to make a long story short, but I'll try. I just re-built this engine due to a broken piston....detonation. This occured because I set the timing incorrectly due to a slipped balancer outer ring. As the slippage can not be guarenteed to be "fixed", I have no idea where my timing has been set over the years, so no baase-line. So I have been playing with it a bit and finally got it where I'm happy with it. Although the best idle is at 38Deg BTDC, obviously it needs to be set lower with a mech-only dist and I've wound up with 18 Deg & 850 rpm with a max just under 38 Deg.

However, because I probably do not have it set as advanced as before, my engine heats up more quickly, my idle mixture screws had to be richened a bit (about 1/4 turn) and the idle stop screw had to be turned it maybe 1/2 to 3/4 turn more than before. This could be causeing a transition problem. I'll have to measure how much of the transition slots are being used up at idle.

I seem to have 2 issues...the "bang/clunck at higher rpms and sometimes a bog/misfire at lower rpms. All intermittent and all more likely when the engine is throughly warmed up on hot days.

As a hot engine requires a leaner mixture, I have given up on the igntion for now and am looking at the carbs. But I think I am looking for something not working vs not set-up right, but perhaps I am wrong about that.

Basic checks show the secondary float levels correct at base of inspection hole. Both Primary levels are a tiny bit below the inspection holes, but after sitting all night (primary bowls are vented)plus losing a bit during by tinkering (pump shots) it seems normal. Checked out both vacuum secondary's for diaphram leaks. None there although I noticed one flowed air easier. Due to different depths of the slots under the checkball. But that's from factory and they worked fine until now.

By the way, there's a miserable job....putting back together a secondary vacuum chamber...that rubber diaphram has a mind of its own!

Oh well.....back to it.....sooner or later I'll stumble onto the answer. Just wish it was due to good troubleshooting and not good luck.