Ah, good plan!

Yes sir. Thats how I used to do it back in the day when I worked as a tech. Very common procedure on the old HEI ignitions. As well as turning the lights off, and spraying windex on the plug wires looking for arcs.

This was the fun days.. And actually still good knowledge that works to date that seems to be long forgotten at times. Thumbs up!

We still do a power balance testing on MPI engines but the kicker is you have to catch any RPM drop very quickly because the IAC will over compensate pretty fast for the drop then help pick the rpms back up ( inputs to ECM - ECM adjusts RPM's) . Another reason why I like the digital rpm gauge.

You ever get this figured out?

I got everything set perfect timing wise. Went through the carb on the slow motor.....changed cap and rotors on both and it's still that way. Going to look closer at the linkage and WOT... not sure how that could have changed but.....

How does the slower engine sound compared to the other? Should be a noticeable sounds difference at idle if it is dropping a cylinder on those motors.

They both sound good. No miss. The linkage looks good... going to swap props next and see if it goes with the prop. Like I said. I put it up perfect last fall... Got me puzzled.