420A 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 the 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.

 

[Locke]

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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.

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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.

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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.

 

[turboglenn]

On an updated note the MegaSquirt is the only stand alone that has factory decoding for 420a triggers (it's a system that Chrysler put together for EXTREME engine monitoring. The ECU knows when the pistons are at 60, 40 and some other odd number of degrees before TDC.

When I spoke with the factory in relation to the Neon triggers the only option besides MegaSquirt is to put hall effect sensor and rare earth magnets on the crank pulley or make a plate with them in it that bolts to the crank pulley

 

[Locke]

I figured as much. The good news (if you want to invest the time) is that a conventional trigger wheel wouldn't be very difficult to make.

 

[VelocitàPaola]

Even though they're not necessary for the 420A, trigger wheels are popular within the MegaSquirt community for retrofitting other vehicles. No need to make one.

4" 36-1 Trigger Wheel DIYAutoTune.com


Since the AF/X or Unorthodox UDP already have threaded holes, I would recommend using one of those rather than the stock pulley. This way, attaching the trigger wheel will be a breeze. My only suggestion is: have the UDP and crank snout keyed so there's no possibility of a misalignment.

 

[92awdgsx]

Here is what I did. I'm running an Autronic SM4 ECU.

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No does anything for the 420a, so I am just making everything myself.

 

[VelocitàPaola]

No does anything for the 420a, so I am just making everything myself.

That's not quite true... there is tons of support for using the 420A with MegaSquirt.

 

[92awdgsx]

But MegaSquirt doesn't have the features or control that Autronic does.

 

[Locke]

MS can handle about everything I've ever heard of anybody wanting.

 

[Oneslow2g]

I hate to try and open a 17 year old thread but I’m wiring up a Haltech Elite 750 to my turbo 420a 2g.
When setting up the ECU what settings do I use?
Would it just be easier to use a crank pulley mounted wheel and sensor?

I would like to make it work on the stock sensors just for the simplicity look.