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Bosch 0 227 100 111 works for 84 and later GTV6's - the ones with Hall pickups as well as all Milanos if they have stock L-Jet ignition. They will also work with Megasquirt up to about 5800 rpm.

 

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There are many Bosch modules in the 0227 series and I once spent a lot of time trying to find which ones were exactly the same and what were the differences between others but I was unsuccessful. Can you point to the data that shows the Beru equivalents?

 

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You can find the electronic catalog here:
https://federalmogul.md/sites/defaul...tion_parts.pdf
Regards

That is a great resource.
Thanks

 

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I purchased a new Bosch 0 227 100 123 module, and the engine would not run for more than five seconds.

On which car?
Did you use heat conducting paste between the back of the module and the heat sink? Was it genuine Bosch?

 

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The above diagrams are for an early GTV6 with an inductive sensor. From 84 - 86 they had Hall pickups which used a module of the type that I referenced in post #1. This is the same module that is used on Milanos. An inductive (VR) pickup must have a module that is designed to use the low level signal that it generates. It will not work with a module that is designed to work with the 12V square wave that is generated by the hall sensor and the hall sensor will not work with a module designed for an inductive sensor.
If you are unsure of what type of pickup you have then remove the distributor cap. The inductive snensor is fired by a 6 pointed star shaped rotor. The Hall sensor is triggered by a rotating metal can with 6 slots cut out of it.

Some of the subsequent posts have muddied the waters

 

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I suspect both from your experience and the above circuits that the 123 is not a replacement for the 111 and someone made a mistake when that was published.
I only ever got good used Bosch modules to work properly but I never tried the BERU. I now longer own a V6 Alfa so I will not be doing any more experiments.

 

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Have you seen a sine wave from the VR sensor? I have not had the exact one that is used on the early GTV6 on the bench but I have had other VR sensors and they made short duration voltage spikes.
It is a mystery to me how you have got yours to work.

 

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Maybe that is why it only works outside of the US :wink2:

 

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That should be a lifetime supply of critical ignition parts.

 

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My experience is with driving 6/7 pin Bosch modules from square wave inputs as provided by Hall sensors and Megasquirt controllers. Bosch made ignition modules for VR sensors and they are a different shape and have different pin out. The 4 pin GM HEI modules work well with VR sensors and are widely available.

 

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0 227 100 111 requires a square wave input which could be from a Hall sensor or a computer. It was fitted to GTV6 and Milano models with Hall sensors. IMO it will not work correctly with a VR signal. If it is used with a computer then it must be one that does not control dwell and spark times.

 

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A few years ago I did some experimenting with different triggers connected to the V6 Bosch module. I triggered it from points, VR sensors and a 123 distibutor. I used a dual trace oscilloscope to monitor the trigger signal and the coil current. I could make good sparks with all of them but none of them controlled the dwell and phased the spark correctly.

The V6 uses a Hall sensor distributor which produces a 12 volt square wave signal. The sensor is horseshoe shaped with a magnet on the inside and the Hall device on the outside. The rotor is a can with six slots that passes though the horseshoe. When the can is in the sensor the output from the Hall is 12V and when the slot is in the sensor the output is pulled down to 0 volts. The ignition is timed so that the slot is just entering the sensor at the correct ignition point.
The output signal goes then to the ignition advance computer which applies phase shift according to rpm and also INVERTS the square wave output signal. This signal then goes to pin 5 of the Bosch ignition module which triggers the coil on the leading edge of the signal. You should take this into account when you are driving the Bosch module from any device. The Bosch module triggers on the leading edge and it computes the dwell angle from the coil current signal.

 

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Hi Graham,
I gave the folder containing all of my V6 ignition information to the guy who bought my GTV6 last year and I am now posting from memory. I think that the mark-space ratio of the square wave has got something to do with it.
There is a good description of the operation of these modules in "Automotive Electric/Electronic Systems" published by Bosch. ISBN 3-18-419110-9

 

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I was thinking about this on my morning bike ride today. The dwell angle range of the Bosch module is about 10 to 70 degrees. It is possible that it can shorten the dwell angle of the input pulse but not elongate it. My points simulator was a reed relay driven by a signal generator and I could control the frequency up to 100 Hz - the limit of the relay, which corresponds to 3000 rpm on a 4 cylinder engine but I had no control over the dwell angle which was most likely less than 70 degrees. Who knows what is the effective dwell angle of an inductive pulse? It is most likely pretty short.

 

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Too bad about that folder - it must be a gold-mine of info!

The guy who got it has been banned from the ABB so we are unlikely to see any of it posted.

 

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I suspect that if indeed there is any smart dwell-control in the GTV6 application, then it's done by the spark computer and not by the -111 module - does this seem reasonable do you think?

I believe that is incorrect. the spark advance computer controls advance and has an rpm limit, nothing else. The behaviour of the Bosch module is described in the Bosch Book that I referenced.
When I ran Megasquirt ignition I first used the stock GTV6 Bosch module and I could not get the car to run properly above 6000 rpm. It turned out that both Megasquirt and the Bosch module were trying to control dwell and the result was a screwed up charge/spark cycle. I posted Megasquirt plots of this in a Megasquirt thread. I replaced the -111 module with a "dumb" module from a Porsche - the one recommended by the Megasquirt designers and which I had overlooked, and the car ran great to 7000 rpm.
I ran the _111 module on the bench with a square wave input and a coil and I monitored the coil primary current with a DC probe that was connected to the second input of the oscilloscope. I was able to measure the dwell angle of the current and determine that it varied between 10 degrees at low rpm to 70 degrees at high rpm. I think that I posted photographs of some of these current plots.

 

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go to abebooks.com and search on 3184191109 in the ISBN field and you will find a number of copies of the Bosch book for sale

 

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I did the testing in the second half of 2017 and I posted some details in post #309 of Installed Megasquirt today

I took some photos of scope traces but it was hard to get good ones so I took to sketching the waveforms along with pulse durations. Here is an example. You can see from my note at the bottom that beyond 5200 rpm the charge current was limited by the rise time and the spark time was 1.2 mSec. Also be aware that the time base is not the same for the different spark frequencies. I shortened it in order to see the pulse shape at higher rpm.

 

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Here is a photo of the current pulse at low rpm. Notice the long delay between the end of the charge and the start of the new one