DIY LTCC or similar system for LT1s

[vilefly]

I like where you are headed. Wouldn't this mean we would have to change the signal coming out of the opti to match the northstar?

There is a junkyard no more than a mile from my house littered with northstars, if you need any northstar stuff let me know. Does this mean we will only be able to use the waste-spark style coils?

To mimic the deltec exactly, we will definitely have to adapt the opti signals to match the northstar's 2 crankshaft sensors, minus the cam signal. It is confirmed that they wired the EST and BYPASS exactly as I imagined. The signals will have to be above and below the zero volt line because of a zero crossing detector built in. So about +5v/-5v peak to peak should work fine.

This would work only for the waste spark setup type coils, unfortunately. But it would get you distributorless. I have a spare northstar ignition module with a bad (shorted) EST input. Just enough to test a signal generator and my crankwheel setup later on. I wonder how much the junkyard would want for one without the coils on it?

[johnny_b]

I can grab some northstar ignition modules no problem, i bet they would only be a few bucks.

The waste spark setup is perfectly fine.
Northstar's have a different firing order than sbc.
looking at delteq's Ignition module that the coils seat on, I wasn't sure if this was the factory northstar module or they perhaps made their own.

Just so we are clear, what I have pictured below is the Ignition Module correct?

[vilefly]

Yup. there is only one like it. You might want to grab the pigtail connectors to it as well.

[johnny_b]

Yup. there is only one like it. You might want to grab the pigtail connectors to it as well.

I will grab a few on saturday and report back.

So from what I understand about the northstar module, it only ever needs 2 of the 3 sensors to actually function. either both crank signals 27* degrees out of phase I think? or one crank sensor (think its 24x?) and the 1x cam sensor. Having all 3(both crank and the cam sensor) allows for faster start?

It seems maybe the 1x cam signal would not be that difficult to convert to with the factory opti-wheel signals?

[vilefly]

I will grab a few on saturday and report back.

So from what I understand about the northstar module, it only ever needs 2 of the 3 sensors to actually function. either both crank signals 27* degrees out of phase I think? or one crank sensor (think its 24x?) and the 1x cam sensor. Having all 3(both crank and the cam sensor) allows for faster start?

It seems maybe the 1x cam signal would not be that difficult to convert to with the factory opti-wheel signals?

Well, what I am not sure of is exactly where in the rotation that the cam sensor sends its quick 1-pulse. Maybe 67.5 degrees after the 1st pulse from the leading sensor. +/- maybe 2 degrees. I am not sure if the ignition module can run on one crank sensor and one cam signal, but it would be cool. We might be able to cheat. If a cadillac comes in sometime, I will grab a better scope pattern from it with pulsewidth measurements if possible.

You know what? I think I will make a round slide rule that will fit inside of a cd case with a 27 deg set of spaced windows so I can check my synchronization at any time. Am sick of getting out the ruler and protractors. Might help me think clearer amidst distraction.

[vilefly]

Here is a flawed picture not to a cd case's scale, but accurate. not done with the overlay. Still using cadillac coil numbering, but we really know that COILS A=1/4 B=2/5 C=7/6 D=3/8. In that order. After #1 TDC, coil B is armed for firing, and is the next to fire.
reluctor template w-TDC-cam sync.png

[vilefly]

Ok, codebreakers.
I found some arduino code that is a cam/crank signal generator for multiple engines. It is called ardu-stim. It has an optispark configuration file in it, but I have no arduino stuff yet to test it. I did not see a northstar one, though. It has alot of engine patterns, though. The code looks like it can be converted for hardware clocking, if scaled properly. I don't know enough about the code yet, but I know that one and zeros placed in a data array should work fairly well.
Here is the link https://gitlab.com/libreems-suite/ardu-stim
Tell me what you think. My arduino mega 2560 arrives tomorrow, and I will start my learning process.