Put a dual point in the car that I rebuilt a while ago. Needed a new bushing, shaft was loose. Don't remember what else I did, but it's in good shape.

Put a new set of Blue Streak points in, and a condenser, not sure of manufacturer, and installed it in the car.

It starts and runs, idles, fine, but when I took it out to test drive it immediately was falling all over itself, stumbling and didn't really seem to want to rev. I didn't push it at all, I'm sure this is around 2000-2200 rpm, not much more, no tach at the moment.

I disconnected the vacuum advance, as well as put a brand new Blue Streak condenser in, no change.

I had used a formula I got off the board here to limit my advance, and welded the slots to get me about 12-14 degrees. With my initial at 20 though, when I bring the rpms up, I'm in the 42-44 range. I don't know how it can possibly be that much, even if I used the wrong value to calculate how much to weld up, I still eliminated a fair amount of travel in that slot.

The other thing I saw was that at idle, the timing light was fine, firing every revolution. Once up in the RPM, it appeared erratic, somewhat in line with the engine sounding like it was missing.

Any thoughts? I doubt two new condensers are bad, but could be. I'm going to try a different rotor, isolating each set of points, but not sure where to go beyond that.

If you are using a "dial back" timing light it may be in the calibration. Timing tape or dampner degrees are a lot more accurate.

No, not using a dial back.

Just thinking out loud. shaft (bushings) tight & axial end play OK? adv plate pivot tight? points gapped correct? It ran OK with the prior dist in there?

Need to get a hold of a dwell meter, better yet find someone with a good old fashioned sun distributor machine and set that up correctly. I've seen brand new distributors loose their mind at 1k and above. Also a machime will let you fine tune the vacuum and centrifugal advance. I used to teach auto shop and i would let guys come in and use mine so check there.

How small is that slot. Your basically saying you have a cam plate with 6deg. X2 to give you 12 at rpm, on top of your 20. If you did the slot like a normal 12deg, that is actually 24deg at rpm and may be why your in the 42 to 44 range.

Yes to all of these.

Forgot to put this in my initial post.

Dwell seemed to bounce around just a bit, but when the RPM was up a little, it was a solid 32.

That probably is the way to go, especially since I'm having issues. I'm wondering if it is something mechanical, as it doesn't make sense that I should have that much advance, considering I welded up that slot.

The issue is finding someone with a machine...

Not sure I follow. The slot is what allows the advance, as the RPM overcomes the spring pressure. Once the pin is at the end of that slot, advance stops. I think the stock advance is in the 20+ degree range. The chart I found on here listed the length of that slot for the amount of advance you want, so I welded the slots and then filed them to get the exact slot length.

Are we talking the same thing here?

He means is the 12 deg, dist degrees (which would show 24 on the dampener) or is the "12" actually crank (dampener) degrees EDIT .340" length on the slots would give you 12 on the crank & .435" would give you 24 on the crank

Got it. I don't remember, but I'm guessing from what I'm seeing that I did 12 at the distributor.

You could try to block one set of points open and see what happens. If no better than try the other set. Also is there a ground wire from the breaker plate to the housing?

I have a Allen and a sun dizzy machine with the specks for all years and models .
If you want I will spin them up and make adjustments, $25 and you pay for shipping both ways. Pm me

That would be your issue then. Put initial at 10deg and see how it runs.

The marking stamped on the distributor cam stop is normally distributor advance for Prestolite and Mopar. So if it is 8 or 12 it gives 16 or 24 at the crankshaft. You double it. The CAP (Mopar emission) distributors starting in 1968 had about 15deg cam stops for 30 advance. That is why initial was a 0 to 2 Deg BTDC.

Is there a reason you think you need 20 deg initial timing?

That is the reason I have so much advance, but I don't think this is the cause of it running so badly. After all, with vacuum advance, the engine could easily be at 44 degrees or more and 2200 rpm moving down the road.

I will move it back to 10 and see if that makes a difference.

It's a Hemi. They like a lot of initial.

dwell should be between 37 and 42 degrees; overlapping points. 42-44 degrees total is way too much.

Dwell set one set of points at a time. Block one set with a piece of matchbook cover while setting the other. I may be wrong but I believe dwell should be 28-32* on each set for a total of 40 -41*.

Ok, I must have been in the wrong section in the FSM, I saw 28-32. It's been many years since I have messed with points!

But, if I isolate EITHER set of points, it runs great. Bring the other set in, and all the issues.

So is a total dwell of 32 enough to cause this issue? doesn't seem like it to me...

I would reset both sets. I had a old Accel dual point and as soon as the rubbing block wore the points would stay closed to long and the car ran poorly. On a lot of performance dual points the point sets have a lot of spring tension so the blocks wear. Make sure you are using lobe lube. If it were me I would set them with a feeler gauge and recheck the timing.