Stalls with electrical loads

Your ballast resistance check from several posts back is too high. 0.5-0.6 ohms cold is the stock spec. But to make sure you are measuring it accurately; short the ohmmeter leads together and record how much resistance is just in the leads. Then measure the ballast cold and subtract out the lead resistance to get an accurate number.

The MSD 0.8 ohm ballast is the closest to stock. The best is an NOS ballast from eBay, PN 2095501.

Very glad your secondary stop screw adjustments helped. Don't be afraid to do it again; it can take several iterations to get it optimum. The exposed primary T slot is not normal so I suspect you need some more adjustments on that.

And I agree with AJ on the timing; no point in pushing up to detonation for a street car and if you are 2 degrees off, you are preeeetty close. Be aware that you can get temp and humidity days that will promote detonation more easily; cool, dry fall days act like lowering fuel octane by 3-4 points versus a hot humid day! So some margin is wise.

I was wondering about that on the ballast, I have three of them, all test around 1.4-1.6 ohms cold. One of them is actually marked "1.2" on one of the terminals. Could swear my 74' Chiltons manual listed it as 1.5 ohms. Are there different values for different years, I would think the .5 ohm jobs would have been for points ignition? I really don't know so I will take your word for it though. I will look into procuring an MSD or NOS piece, wouldn't hurt to try one. Thanx again for the inputs, living in Florida I am well aware of Winter and Summer settings on the Carb and Ignition. What feels great at 70 degrees will rattle at 95 ambient.

By the way ran it with all accessories cranking, left it in gear at every light on the way home several times this week, never hiccuped once!! Still hard to believe a minor adjustment like that put it right.