Programmable Delco Ignition Module

[HQ355]

Complete Chinese VT distributor are about $80 on eBay, housings are good quality it's just the electronics that arn't the best. Just swap in some good hall switches down the line

[Holden202T]

yeah but if you have a PRE vt dissy already you only need the module linked above and the right rotor button (im sure all auto parts stores can get this easily enough) then you can bolt it into the older dizzy.

as for the cam sensor signal, it uses it every revolution to know when it is the start of the sequence, so say its lined up with cylinder 1, when the cam signal is found, the ignition module knows that the next crank signal is cylinder 1 and then has programmed into it the firing order 12784563 so it then fires each coil in order of that as it gets all the rest of the pulses, then sees the cam signal again and knows to go back to the start .....

and IF you have a failure or some issue that misses for that revolution it will always recover when going back to the start of the sequence at the right time from the cam signal ... the only downside to this is if you loose the cam signal you will have a no run situation.

and if you wanted to do something like the rotor button as a cam signal ... there is a screw on the top holding the brass stripe on isn't there ? remove it and replace it with a piece of steel then your reluctor signal will work fine.

if you wanted to go totally dizzyless then there is the option of crank mounted trigger wheels, these will allow wasted spark but not sequential spark unless you have a cam signal ... I went down this path when converting the 202 to run 6 LSx coils, and for the effort of a cam sensor I just went for wasted spark, and now I have a lot of room where the dizzy used to be

[immortality]

Getting rid of the dizzy on a 304 with bananas would be a dream.

Would a missing tooth type crank angle sensor work?

I was thinking of fitting a gilmer drive ( I hate V belts) which would possibly allow the incorporation of a toothed trigger wheel into the alloy pulley for the AC.

[Holden202T]

missing tooth trigger is what im using on the 202 and it works fine, but that said, you need to be able to fabricate and mount a sensor in the right spot for it.... I haven't really looked at a V8 to see but its certainly an option.... and there are a multitude of trigger wheels available online! I went for a 36 - 1 tooth 6 inch wheel, that fits the 202 perfectly and the right number of slots/teeth... 36 divided by 6 = 6 .... so provided you can find a wheel with the right amount of slots for a V8 and the right size to bolt to the balancer your in business...

example: http://stores.ebay.com.au/trigger-wheel ... 34.c0.m322

[VL400]

How does the module use the sync mark does it use it every time ir does it only use it for initial start up then just calculate off of the main pickup I'm just thinking about any possible movement in the cap

So long as the movement is not excessive and changes when the pulse occurs in relation to the main trigger (ie the movement is enough to move it either side of the main/primary tooth) it is ok. I dont time the sync pulses, they only must occur at the correct primary trigger tooth count. All primary teeth are counted so the modules expects to see a sync tooth at a certain point, it sets errors if they are not at the correct time. The primary trigger is timed though, and using a predictive algorithm based on the engine velocity means it needs to occur in a configurable window of time to be valid - it will detect a missed primary trigger within a single tooth, rather than needing a full engine cycle for the sync event to occur to then see this at the wrong time. It also means noise can optionally be ignored. There is more processing power in the ign module than the ECU

That sounds like an idea. Mount something through one of the original spark plug terminals maybe? Is the timing of this sensor critical?

It can be anywhere, all configurable as to where #1 is in relation to the cam signal.

Would a missing tooth type crank angle sensor work?

A 36-1 trigger works for an 8cyl too, on holden202t's 6cyl the module is configured to skip 11 teeth (36 / 3 = 12 teeth per cyl, 11 teeth between each). On a 8cyl it would skip 8 with every 9th being a reference tooth for the ECU (the ignition module handles this sending only the reference teeth to the ECU, but using all the teeth for various functions internally).

[immortality]

Holden202T do you have a picture of your crank trigger wheel?

Definitely sounds like a lot of potential here.

[Holden202T]

see here: http://pcmhacking.net/forums/viewtopic. ... =50#p28803

on the page after that one is more pics of the sensor also.

[immortality]

Cheers. That looks too easy unfortunately I don't think they make one big enough to suit a 304 Harmonic balancer OD

VL400 can you please PM more details etc for this ignition module.

Cheers

[Holden202T]

What size is the 304 balancer ??

It only just needs to be big enough so the teeth are larger than the balancer!

[monaro308]

I think you would have to machine the centre of the trigger wheel if it was fitted between the pulley and balancer because the 1,2,3 grooved pulley has a little spigot that sits in the centre of the balancer.
It could be mounted in front of the pulley using spacers.
If you have AC and P/steering and the original clutch fan, i know on mine the fan blade is very close the third pulley.