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@Mattax About HEI coil current limit. It works by turning off coil drive transistor when current exceeds set limit, and back on when current is under limit. Switching happens in fast repetive manner, such that resulting current is smoothly regulated. It takes only one small transistor, and a low...

If you have a timing light, put it on #1 and view timing when cranking. It does two things, it will indicate plug is firing, and timing. Four volts at run is very low, that may indicate bad bulk head connection for ignition circuit. Run power from battery hookup for test.

Good plan.

IGN1 and IGN2 are at ballast resistor. They come from ignition switch. One powers when cranking, other in run. Just connect together and connect to pin 86. Solenoid has start wire, but it is only powered when cranking. Battery power at large solenoid stud is often electrically noisy when...

Relay pin 86 should go to IGN1 and IGN2.

Resistor adds loss, decrease time delay. Diode provides path for stored coil current to circulate, hence holding relay closed longer. A relay hold current is typically 1/4 normal operating current. A scope can be used to capture hold time, by triggering key switch falling signal, and viewing...

I can see using a diode on relay coil, to slow down relay contact release on start to run transition. Diode polarity is important, it must be reverse biased, cathode at + terminal of relay coil. Addition of diode may provide about 100ms of release delay for transition, for a worn ignition switch.

Signal is better described by voltage not current. Signal voltage is proportional to RPM. Reluctor swinging past magnet biased pickup coil, generates EMF voltage related to change in flux over time. Current is that voltage divided by load impedance. That load, is circuit that turns ignition...

Plug #3 possibly shows signs of leaking due to insufficient torque. Same with #2.

Bosch cube relay relay current is typically 0.11A at 12V that's about 1.3W. A Joule is a Watt second. A guess for required hold time is likely 50 to 150 ms. Using 100ms, requires at least 0.13J. Calculated number above in post 9 is much smaller. Joule calculation is energy based, assuming...

A cap may help, but needs charge time. A quick startup might not provide enough time. I have a feature to in my ecu to run fuel pump couple seconds, and then shutdown if no engine crank. It purges fuel system. I can tell by sound of fuel pump. If haven't driven for months, will give second...

A reverse biased diode, in parallel with relay coil, will freewheel coil current, resulting in slow opening of relay contacts. This is often enough to avoid interruption. Some relays have a built-in diode. It is important to observe correct wiring polarity of coil. If you have a scope, it is...

I am not familiar with FiTech or any other OTS system. He are ideas that may help. 1. System setup is often done with help of conventional timing light, to set base timing reference so FiTech agrees with same timing value. That will answer question about dist vs crank, most likely crank. 2...

Before alternators, generator regulators often had over current cutout or regulation. It was a normally ON relay, with both coil and contacts in series with output. When current reached max design limit, contacts would open, hence current regulation. Generators needed current regulation...

Yes, but looking at contacts open and close is different than using a multi-meter and looking for change of state. Powered contacts will have voltage across them when open, and go to low voltage when closed. Check grounds with meter, by measuring back to battery (-). Voltage should be near...

Most often, "open contacts stop motor".

I drive daily with 13:1 on 87. Runs great! EFI, direct injection. :)

Do islands function to open and close contacts? Figure out a way to test continuity or measure contact voltage. Verify motor body has ground with meter. Momentarily jumper park contact as test, to see if motor runs.

When you go to test, take wiper arms off. Only replace when action seems correct. Park contacts open at park position. In run, park is over ridden by wiper switch. When wiper switch off, park drives motor to park and kills power. If park contacts are corroded, eroded, or bent, park won't happen.

Still don't see contacts. More pictures please.

Picture of contacts on inside of cover, may reveal something.

Missing magnet may be hiding on flyweight.

I think engine is tight cold, and or, leaking vacuum when hot. RPM is increasing, mechanical advance increasing with that. A good way to test is gather timing vs RPM at low end. You should find relationship nearly same vs temperature. Vacuum advance plugged at carb, open at distributor, or...

Another way of thinking about it: Points close and coil primary charges, when points open, coil discharges, coil + to battery completes circuit of electrical circuit. Inductance and resistance in wiring to coil, results in limitation. The capacitor firms up coil + voltage during transient...

A short story about what that capacitor does. It provides a close AC path, to ground. Without it, path is back to battery +. That 3 to 4 foot path is a good antenna. In electronic circuits it would be called a bypass capacitor.

At best, automotive alternators are 60% efficient. Efficiency could be increased some, with synchronous rectification, using mosfets instead of diodes. That would add cost and more parts. Permanent magnets, instead of electromagnetic field, and more complex power conversion instead of simple...

Field intensity increases with amp-turns. That is product of current and winding count. There is a limit, due to saturation of magnetic circuit. Increased field, increases alternator output voltage, but output current, is load related. Regulator action controls field current dynamically, and...

Early regulators are basically a normally closed relay contact between IGN and FLD. Coil of relay is on IGN and ground. When the IGN voltage is about 13.8V, the NC contact opens cutting field. After a short time voltage drops, and NC contacts close again, then open as voltage hits 13.8V...

If battery cable ground to engine fails, the smaller ECU ground at battery will attempt to carry starting current, and smoke, perhaps a fire. Rare, but it has happened.