Setting up 420A crank trigger for Haltech...

[turboglenn]

Does anyone know how to configure other ECU's for the 420's triggers? It's weird having 2 sets of 3 teeth 180* out from each other on the crank, and then the CAM angle sensor has 3 magnets (triggers) So i've been confused on this one.

I can't tell if it should be a multi-tooth and where or when the "missing teeth" would occur, I have no clue what corresponds to what as most have triggers that are evenly divisible by the amount of cylinders. But, i haven't studied the motor in depth either. I've just been wanting to get a wire harness built for teh haltech to run on My girl's neon (turbo SOHC). My plan is to have a wire harness built for what ever ECU We actually purchase for it, but i will probably set it up for a haltech since i know the system so well.

Anyone contact me if you have knowledge of the triggers and what edge they trigger on contact me.

[Locke]

The ECU uses the 60° notch as reference. In the subsequent groups of trigger notches, the first notch represents 69° BTDC, the second 49°, the third 29, and the last being 9° BTDC.


The cam sensor switches high on a north pole and low/off on a south pole.

Both cam and crank sensors switch +5V.

[turboglenn]

I pm'd you but I'm taking this as follows for a trigger setup

Trigger type = multi tooth (a.k.a. Nissan) with missing teeth for home reference.

Trigger Edge = falling ..... or it could even be rising on all other edges, while using the falling edge of the missing 60*'s as the home and not need the cam sensor for that. Hell you could even grind off the 3 extras on each side and leave the 2 rising edges at 180* out and then the cam as home...too many options i just can't figure out the one that it's intended to be seen as.

No other motor has caused me the confusion on triggers as the 420a has. I read that dodge put the triggers this way so the ECU could see exactly where it was all the way through each pistons stroke and not just a signal event to tell it to fire in "X" amount of degrees.

Home trigger type (reluctor/hall effect?) also triggering on a falling edge.

But the thing getting me is there's enough trigger events (8 or 16 if you're having it count every 2 revolutions) to be evenly divisible by 4, but the way the 3 other edges on each side are setup, how do you have the ECU treat them? This one is seems real tricky to me for some reason. I'm sure if i started rotating the assembly and reading the triggers on a scope or even a meter i could figure it out a little easier, but for now I'm still a bit confused, and i don't have the means to get the assembly up and rotating just to experiment in the basement with triggers. (my last house had a big enough garage that i had a full engine test stand i could run them on )

[Locke]

As per our PM, here is the crank/cam signal correlation - so no need to scope the outputs. Both cam and crank sensors are Hall Effect sensors.



I would not recommend modifying the trigger wheel, as it is machined into the crank's counterweight. I hope this information is helpful to you, and if you do get it figured out, please post how, so others may benefit.

I wish I could be more help.

[turboglenn]

Cool, thanks Locke, As soon as i figure out how to hook most of your standard stand alones to it, I will post up the setup info (it probably won't be real soon because the motor is out of the car at the machine shop now)

But i will post as soon as i can, thanks again!!!!!!!!!!!!!

[Slippi84]

Some of the stuff you guys rig up is mind boggling you guys need gf's or something j/k

What would be a practical laymens terms use for a trigger like this?

[Ajax]

Glenn if you are planning on running the Megasquirt, it's already setup to running the 420a code with stock sensors. Catalog Index - at RS-Autosport.com - Real EFI for Real People on Real Budgets but they are out at this point.