Has anyone had any trouble with misfiring due to too low static timing?

I recently replaced the gasket underneath the distributor, reset base timing, and adjusted my bin to reflect the slight difference. I ended up with 8* initial timing, where it was 10* before. Now I'm noticing my engine breaking up slightly at WOT that wasn't there before. I'm wondering if the 2 degrees less static timing is causing the rotor to be at a different position relative to the distributor terminal than it was before, causing it to miss.

I will be going through the ignition system, replacing cap, rotor, plugs, and wires soon.

Just wondering if anyone else has ever run into this problem. Total timing gets to be around 36-37* of timing at some points.

 

Might be now that you have a new gasket that it's not vented and causing ionization, or it could be just a phasing problem, also you did disconnect the EST wire before setting the base timing? I've never had the problem but I have seen ionization happen on many cars and/or phasing problems, for my car I just set it a 6* before, engine warm, idle a 700rpm, I'm just at the limit with vacuum though at that idle.

 

The gasket is at the intake manifold. The cap is still vented through the mesh screens at the bottom of the dizzy body.

Yes, my static timing was set properly. Engine warm, bypass disconnected, at idle.

You say phasing can be an issue with this style of distributor? There is no adjustment, except for setting static timing higher, with the tradoff being harder hot restarts right?

 

As long as the distributor base is set the same in the calibration, and, the minimum and maximum SA values in the calibration are correct, there is no issue with the distributor phasing.

So if they are all set correctly it is likely something else. Could be old spark plugs, wires or cap, coil. If the tach starts to jump at the same time that is a sign that there is something in the secondary ignition area that has a problem.

RBob.

 

I didn't notice my tach jumping around. The log shows variations of maybe 100 rpm in the range where it was occurring. That's probably from when it was breaking up.

You're talking about jumping around like its momentarily losing its signal and heading straight for 0 right?

here's a datalog of the run. Look around line 75