How do you test a point distributor?

Test for continuity between the block and the stationary point attached to the distributor plate. Rotate the engine until the points are closed. Use the multi-meter to test for a good connection between the points. A slight gap when the points are supposed to be closed will keep your machine from running.

Is the distributor similar to a points ignition system?

The distributor retained the same housing and vacuum advance system that was used on points type ignition systems. The theory of operation is very simple. The reluctor is similar to the rotor of a points type system, except it has vertical vanes that protrude from the side.

When does the ECU have actual control of the dwell?

Mapped dwell (ECU has actual control of the dwell)- This is when the ECU sets the dwell based on an internal map. The main variable is battery voltage as this has a major effect on the time needed to allow a coil to reach our target current level. The map has to be programmed correctly for the particular coil used.

When did they start using electronic ignition points?

The earliest ones used breaker points. Chrysler made an electronic ignition standard in 1973, which used both a mechanical and vacuum advance. These distributors used a variable reluctor type sensor, much like the later GM HEI and Ford Duraspark.

Is the MegaSquirt a distributor based ignition system?

Distributor (a.k.a. dizzy) based ignition systems are usually the easiest to take control of, and support for standard distributor based ignition systems was built into the MegaSquirt (with MSnS-E) and MegaSquirt-II so there is a huge amount of support there. So what exactly am I calling a ‘standard distributor based ignition system’?

What is the est / spout signal on a HEI ignition module?

The EST/SPOUT signal is the same as is found in many factory ECUs. It is a +5V square wave trigger that is used to drive an HEI ignition module. Because of that, it can be used to control timing on a GM Small Cap HEI or Ford TFI distributor.

Why does my ignition coil charge faster than the ECU?

The ECU will not know you have done this and will still turn the coil on for a certain time, if your new coil charges quicker (lower inductance) then the coil or ECU will be damaged. If a slower charging coil is fitted (higher inductance) you will get a poor spark.