Help needed! converting 202 to delco

Converting To Delco ECU From Carby Or Other Injection Systems
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Elijah Bruce
Posts: 63
Joined: Fri Jun 25, 2021 7:47 pm
cars: 1975 Holden Kingswood Utility

Help needed! converting 202 to delco

Post by Elijah Bruce »

g'day everyone, hope all is going well.
Bit of a background here (skip if you want). Im in year 11 doing my 'research project' for school. My aim is to rebuild a nice 202 for my HJ ute for when i get my p plates. Now the stock 173 didnt have enough go for me so i've already bought a complete black 202 motor and will be using the internals out of that and putting them into a red 202 block (for an emmisions gateway). Now i want to go efi as i dont have a lot of $$ laying around being 16 years old and funding this all by myself. I want to go with a delco ecu as i will need the tunability with a bigger cam etc.

Ok, so here is my issue. It's all a bit overwhelming reading all the different ways to do everything. I've read HOLDEN202T's guides and while they are mighty helpful for when i get this in the car. They didn't go much into detail of what i might need to buy and wire up. I was wondering if anyone is able to give me a hand to get this project of mine on the road. I know i will have to lock the black motor dizzy and install a pulse generator and hack a VN throttle body onto my vk intake.

Im definetly new to this, so any help to point me in the right direction would be great. Cheers
'quipt4it
Posts: 675
Joined: Sun Oct 28, 2012 12:57 pm

Re: Help needed! converting 202 to delco

Post by 'quipt4it »

Hi and welcome to the forum.
This page sums up most of what you should need to acquire:
viewtopic.php?f=15&t=4&hilit=convert+20 ... &start=210

NVRAM and board from here:
viewtopic.php?f=14&t=3612

USB Comms Board (for the '808 ECM):
viewtopic.php?f=14&t=3613

You will also need sensors such as CTS, IAT, O2 (Oxygen Sensor) or Wideband. Also an 'in-tank' fuel pump with return line for fuel from the fuel rail.

There is also the Getting Started Guide, which is a mine of info and required reading:
viewtopic.php?f=7&t=655

As usual, the FAQ green button in the top right of screen should help with specific topics.
I'm sure this will be an interesting experience for you.
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Elijah Bruce
Posts: 63
Joined: Fri Jun 25, 2021 7:47 pm
cars: 1975 Holden Kingswood Utility

Re: Help needed! converting 202 to delco

Post by Elijah Bruce »

Thank you very much! That’s what I was looking for. I appreciate it!
Shake N Bake!
'quipt4it
Posts: 675
Joined: Sun Oct 28, 2012 12:57 pm

Re: Help needed! converting 202 to delco

Post by 'quipt4it »

Best of luck with your project.
The team are always here to help. :thumbup:
heff0018
Posts: 888
Joined: Tue Apr 21, 2015 1:42 pm
cars: CL valiant charger, VH valiant charger

Re: Help needed! converting 202 to delco

Post by heff0018 »

Gday Elijah, check my posts. I have asked all the stupid questions which may save you some time and headaches. My conversion was for a valiant 265 but the only big difference is that I was able to use an ELB distributor and didn’t need to lock a vacuum advance dissy.

viewtopic.php?f=15&t=4104

If you can source a JE Camira loom it will make things real easy but they are getting hard to find.
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Elijah Bruce
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Joined: Fri Jun 25, 2021 7:47 pm
cars: 1975 Holden Kingswood Utility

Re: Help needed! converting 202 to delco

Post by Elijah Bruce »

g'day. That has also cleared up a lot of confustion thanks.

One thing that i am stuck on is after the dizzy is locked (and timed to 10 before tdc) how the delco ecu actually controls the advance of spark. In Holden202T's guide it seemed he still had the plug leads going to the dizzy. So im a little confused on how the ecu controls timing if the plug leads are all headed to the dizzy which has been locked?

Cheers
Shake N Bake!
'quipt4it
Posts: 675
Joined: Sun Oct 28, 2012 12:57 pm

Re: Help needed! converting 202 to delco

Post by 'quipt4it »

The distributor will still function as a normal distributor.
All you are doing is locking out any advance which would previously have been done through advance weights/ or vacuum control.
The ECM will perform the functions of advance/ retard based on a MAP of KPA (engine vacuum) vs RPM when set up with the module interface.
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pman92
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VE Ute
Location: Castlemaine, Vic

Re: Help needed! converting 202 to delco

Post by pman92 »

The distributer is only distributing the spark from the coil to the correct cylinder (hence the name distributer).
The ignition timing is controlled by when the coil primary is switched off (and the magnetic field in the coil breaks down, "inducing" the high voltage into the secondary).

In an old points system the device actually switching the coil on and off (the points) is in the distributor, hence turning the distributer obviously changes the timing.

With the blue/black motor electronic ignition, the ignition module (mounted externally on the side of the distributor) is now turning the coil on and off, BUT it does so directly from the signal it receives from the reluctor pick-up inside the distributor. Timing is still adjusted by turning the distributor. The distributer still has mechanical and vacuum advance built in.

When you lock the distributer and use it with the Delco, the signal from within the distributer is no longer directly related to ignition timing.
1. That reluctor inside now runs a signal to the ignition module.
2. The module converts it to a "Reference" signal which goes to the Delco.
3. The Delco knows when the reference signal occurs relative to crankshaft position (hence it being the reference) - this is "base timing".
4. The Delco sends an EST (Electronic spark timing) signal back to the ignition module, which can be at any time it desires.
5. The ignition module switches the coil on and off relative to that EST signal

Setting the distributer is only required once (to set the base timing). That's just so the reference signal actually is when the delco thinks it is.
EG. it might be trying to achieve say 30 degrees with the EST signal it sends back, but if the reference signal and reference angle in the calibration don't match up by 8 degrees, the actual ignition timing will end up being 22 degrees or 38 degrees (depending which way it is out).

10 degrees is the norm, but you can actually change that reference angle to anything you like within the calibration
VR-VY Holden BCM Simulator: View Post
MrModule.com.au
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Elijah Bruce
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Joined: Fri Jun 25, 2021 7:47 pm
cars: 1975 Holden Kingswood Utility

Re: Help needed! converting 202 to delco

Post by Elijah Bruce »

Perfect explanation! Thank you very much!
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Elijah Bruce
Posts: 63
Joined: Fri Jun 25, 2021 7:47 pm
cars: 1975 Holden Kingswood Utility

Re: Help needed! converting 202 to delco

Post by Elijah Bruce »

Hello everyone! Back again. I've made good progress thanks to the previous answers. I have the camira ignition module and delco unit with a vp loom. Now time to sort out the wiring & sensors!
Now my questions are that in Holden202's original post he mentioned to cut the dfi module plug off the vn/vp loom. Now where do those wires go to? Should i have an dfi module? From the photos it seemed that they went into the coil but i could be way off.

Now for the bigger question. Is anyone able to reply with a list of the sensors that i will need and the locations that they should be installed?. Just need to know the locations as i will be welding up the holes in the VK manifold that will not be needed.
Some info on my build if it helps:

mild black 202 with VK Injection
Vp loom with vp delco 808
will be using the VK clutch fan (no thermos)
Standard water pump
Wanting the delco unit to do just fuel/spark


Hopefully this will be the last info i need.
Cheers!
Last edited by Elijah Bruce on Tue Jul 20, 2021 10:58 am, edited 1 time in total.
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