Electronic Ignition

[antus]

My next project is to put a delco on an isuzu 4ze1 2.6l 4 cylinder. Ive collected some info about the camira ignition module from here (thanks VL400) and know that its essentially a 0v crossing detector, that converts AC waves from the reluctor to a 0-5v square wave more like a hall effect sensor.

Now I understand that pretty much any system could be converted to run this module, or maybe even feed direct to the ecu?

Here is a pic of the distributor I need to interface. Its an optical pickup, but the 4 slot system would make a close enough wave that I figure it must be usable. I guess I'd need to feed it power, and if the signal crossed 0v then it would probably 'just work' with the camira module. Being an LED though, I bet its a low voltage signal that does not cross 0v. Would it be possible to use some other 0 crossing detector with a 1v bias or similar to get the right output that is delco compatible?

[delcowizzid]

yeah thats very similar to the RB30 system mate XRpilot was triggering a camira module using a couple of transistors connected in there somewhere he hopefully sees this and can give you some ideas to test.

[XR Pilot]

Here is the setup I benchtested. My MS Paint skills suxor but I think you'll be able to work it out. I had this setup triggering on the car with a bodged up setup running on the original ecu, with a sparkplug connected to the coil to the camira module. The result was a big fat blue spark over an inch long to the rocker cover. When the spark plug lead fell off the rocker cover (bet you seen that coming ) near my hand I freaked out and pulled power to the coil, but this left the module powered and fried it (I'm assuming this is what fried it anyway). I haven't had a chance to test it since, but my biggest concern is the RB30 uses a wider slot on cylinder 1's trailing edge. If the trigger comes from the rising edge for the delco then I should be able to use the CAS unmodified, otherwise if its leading edge cyl 1 will have retarded timing to the rest. Not good..

I think I originally used 2N5551 NPN transistors and 1K ohm resistors, but I am no expert so you can prob find a better and more reliable combination. Basically the way it works is when the input is low then the first output is high, which powers the second transistor to pull the second output to ground. When the input goes high from a squarewave pulse then the first transistor pulls to ground, pulling that output to ground which then turns off the second transistor, allowing that output to go high. From memory I used 5V reference for VCC, but I guess it could be modded for 12v usage.

If you want more info you can find me on MSN, being the admin you should have my email addy from my profile

[Apples]

Hi,
If the back of the slot is what is used how about flipping the disc over so front edge becomes the back edge.
I know when you rebuild a VL dizzy and put the disc in upside down the engine will run but not right.
just a thought.
Or make a new disc.

[XR Pilot]

*Smacks forehead* Why didn't I think of that. Its been ages since I had one pulled apart and forgot they where flipable!

Fingers crossed it can be used unflippable so I can swap back to the ECCS system easily (biggest reason for keeping the dizzy unmodified is because the skyline is my daily)

[antus]

I knew something like that must be doable. As soon as I can find some time i'll make one up and put the scope on it and report back. Thanks!

[VL400]

Nice circuit there XR Pilot very simple! The only thing that may cause an issue is it does not return to zero volts in an idle state. But the module should be seeing a zero crossing on each pulse so in theory should be happy. Need to find a test vehicle to give this a run!!


If the camira module does not seem to work as expected the alternative is to use a V8 module as that will work perfectly with the optical sensor. They just cost more. Need to get the dizzy setup correctly though so that the spark is delivered at 10deg (or whatever you want) during cranking - from my understanding it uses the leading edge of the slot to start dwell and the trailing edge to deliver the spark. During normal run the leading edge is what the ECM triggers off so whatever deg BTDC that ends up is your ref angle.

[antus]

according to http://www.ehobbycorner.com/pages/tut_transistors.html the transistors you've drawn are PNP, but according to the 2N5551 datasheet they are an NPN part. Are they drawn the wrong way? Just figuring out my shopping list now.

[antus]

have been thinking futher about this... what sort of coil did you have connected prior to the module burning out? i had trouble with the module burning out in my gemini also, until i put that weird looking camira coil in. All the docs show the pinouts for the camira coil with nothing special in it, but I do wonder if it has some kind of current limiter or something that protects the ignition module? I would like to use a better coil but im too scared to risk the module and getting stranded. What other coils have people successfully run with a camira module?

[Holden202T]

msd makes a camira coil .... i dunno how it differs to the original but it might be a better option ?