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Borstlap
V4 Fanatic

Norway
304 Posts

Posted - 07 Jun 2013 :  22:16:24 Show Profile Reply with Quote
This topic is about a programmable ignition I built in my Sonett, but the story begins with something different: an inlet manifold.

After having bought my Sonett in 1999 and browsing the www for Sonett-fan websites and parts suppliers, I found two pictures (on the site of the no more Motorsport Sweden) of an engine that looked very exciting because of all non-standard parts that were attached to it.



They were pictures of a race engine built by Jack Lawrence, one of the V4 gurus in the US. I had vague plans and wishes for a better running and more powerfull engine (the one in the Sonett didn't run that well in those days) and became quite intrigued by the carbs installed. After some detective work I discovered that they were Weber 40 DCNFs. It turned out that these were also used by Saab before they changed to DCOEs, so these were the ones I should go after. After some time I managed to buy a set (with accompanying VW-Beetle manifolds) on Ebay and then I could get started with hacksaw and sanding machine on a standard single throat V4 manifold; DCNF manifolds are made of either unobtanium or veryexpensium so one needs to be creative. What's more, they are unsuitable for use in a Sonett.


The engine in my Sonett lies horizontally instead of that it tilts backover as in a 96/96, so a manifold like the one in the picture is not really an option. So I started measuring and came to the conclusion that the dizzy was a major obstacle for getting the rear carb positioned properly; this is quite critical because of the bolts that screw down the manifold, as seen here below.

The motorcycle ignition contraption as used on the Jack Lawrence engine was out of my league, so my project ground to a halt. Then about a year or so later someone here on the forum put up the question if it was possible to use the fan pulley for use in conjunction with a Megajolt ignition. This got negative advice of course, but my interest was aroused and after some websearching I found the site of the makers of Megajolt, www.autosportlabs.org. This looked interesting, but would it be possible to use the balance shaft pulley as a mount for the needed trigger-wheel that is essential for the operation? Not long after I found on the Swedish Saabclub site a topic from a Finnish guy who had built a 96-Turbo and had used a Ford ECU for controling ignition and fuel injection. The ECU used a trigger wheel mounted on the balance shaft pulley for crank position information. The only thing that kept me from getting started was my personal financial crisis. Starting in 2009 I collected the not too expensive parts bit by bit and started after a while I could start tinkering with the trigger-wheel and metal profiles in order to get the VR-sensor in position. I have a spare engine block, which was very convenient for this purpose.

For starters the trigger-wheel and sensor. The bracket is bolted down by using two of the bolt holes used for screwing down the engine's front plate. The threaded rod makes positioning very easy. From above it looks as follows (apologies for the unsharp pictures; autofocus can be a curse ).


After this dry testing it was time to test for fitment on an engine that could run; enter the 96:



For this purpose I removed the cooling fan from the pulley; it is quite in the way and I could do with some space. The long ago bought original electric 99-Turbo fan was tie-wrapped to the front of the radiator and kept things nice and cool. The test run went well, so then it was just to get started with getting the electr(on)ics in place for testing. After a while things looked like this:

Left from the red screw driver is the Edis-module. This receives positioning information from the trigger-wheel, sends out a signal to the ECU, receives a signal back from the ECU and sends a signal to the coilpack, here standing on fresh air duct. From there it is down with to the plugs. I managed to grab the plug cables on Ebay for less than a fiver; brand new and originally meant for use on a Fiesta. The Edis-module has a limp-home mode that comes alive when it doesn't get a signal from an ECU. Trying this I got sparks on the plugs, so I was on track. Last year I managed to get an old no longer in use laptop with an old fashioned COM port from work and finally during autumn the Megajolt itself.

Soldering the Megajolt together went ok, but there was a snag that costed more than a month to sort out. Megajolt sells in two versions, one that works with a MAP-sensor and one with a TPS-sensor. Mine is the MAP version. When testing I got a weird pressure reading, stopping up everything. Finally it turned out that one of the pins of a processor had folded up during pushing it into place , resulting in a wrong signal. After this was sorted out I got issues with the vacuum due to the carb of the 96; it is a worn out and air leaking Fomoco. As this would not change I decided to take the plunge, remove the nose from the Sonett and start installing. There was a nice weather period at the end of March which I used for getting the car out of the container and remove the nose. Things got serious now .

To be continued.

Edited by - Borstlap on 07 Jun 2013 23:07:35

Borstlap
V4 Fanatic

Norway
304 Posts

Posted - 08 Jun 2013 :  10:11:10 Show Profile Reply with Quote
So there started the process of getting everything transfered to the Sonett. It started messy with long loops of wires all around, but things got tidier with the final result as below. The sequence of the pictures is how the signals go through the system.

It starts with the sensor reading the position of the trigger-wheel on the crank case pulley. Just outside the picture the cable enters a flexible hose that is also used for the earth wires coming from the 3 electric components involved; these have to be earthed at the same place in order to prevent signal interference. The earth connection of the engine's earth strap is used as a central attachment point.



The hose runs towards the bulkhead and then down towards the hole drilled for getting all cables into the passenger compartment.



The T in the loom (between the red tiewraps).



The signal coming from the sensor travels further to the right to the Edis-module. This is a part used by Ford to control the ignition. It is kept in place by magnetic tape. The Edis-module receives the signal from the trigger-wheel sensor (telling the speed and position of the crank case) and sends a signal (the PIP-signal) to the ECU; in this case the Megajolt. The PIP-signal travels through the hose to the T, where it enters the passenger compartment, ending up in the Megajolt.



Left from the MJ the vacuum hose running from the inlet manifold is seen. The casing is also held in place with magnetic tape.



On the passengers side is a place that almost totally obscures the MJ when it is in place.



The MJ send a signal back to the Edis-module (the SAW-signal). This signal tells the Edis-module when to give a firing signal to the coilpack.




The coil pack is attached to the bracket between the bulkhead and the bonnet release mechanism.

I wanted to keep the numbers of holes that had to be drilled as low as possible and managed to keep it down to only one. The vacuum hose runs through the hole that was used for the free-wheel handle.

From the Edis module runs a hose along the hydraulic bottles with 3 wires that can be used for controling external appliances.

The vacuum pickup at the inlet manifold's side. I used the brake booster connection.



As the Weber 32/36 DGV carb I use has ported vacuum it was needed to get a pressure signal directly from the manifold instead of tapping into the hose of the dizzy's vacuum advance. Using the intermediate plate works, but the mechanical vacuum meter I installed shows an unstable needle when idling. Maybe it is due to a stuck PCV valve, but I am planning to tap straight into the manifold with a length of tube picking up vacuum at the bottom of the manifold between the carb throats. The MJ doesn't visibly suffer from fluctuating vacuum reading, but I just want to try to get it even better as it is now.

So far the installation, next actual driving.

Edited by - Borstlap on 08 Jun 2013 12:28:04
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Borstlap
V4 Fanatic

Norway
304 Posts

Posted - 08 Jun 2013 :  14:45:22 Show Profile Reply with Quote
It looks as if the format of this forum doen't allow for showing the viewer of a film on Youtube, so we are stuck by just placing the links (if it is possible, does anyone know how?). I recorded the first test drive I made with the bin that is i use now. First is a picture of the bin with all the programmed advances. The bins are divided by absolute pressure in KiloPascal (KPa) and rpm.



So time for the driving. The first clip is downhill and then motorway driving at 80 and 70 km/h with some accelerations inbetween.

http://www.youtube.com/watch?v=ZwoA6-C1oek&feature=player_detailpage

Next is just for fun flooring it in a tunnel; enjoy the Highgate exhaust sound .

http://www.youtube.com/watch?feature=player_detailpage&v=zeQAwFgkqv0

And last the same road back with uphill at the end.

http://www.youtube.com/watch?v=sC54EPePraQ&feature=player_detailpage

Compared to the old ignition consisting of the dizzy with Pertronix and blue Brazilian Bosch coil the engine is markedly more responsive between 2600 and 4000rpm, being overtake speed here in Norway. I used to be inclined to shift down to 3rd when somebody in front of me drove 70 km/h where it is allowed to do 80, but now it is just to step on it and go. There is a small penalty to be paid in cold start performance when the car is driven regularly and there is fuel in the float chamber. With the old ignition it starts at first compression stroke within a second (no joke), now it takes a second or so longer. A small price to pay for much better performance there where it is needed.


Edited by - Borstlap on 08 Jun 2013 15:20:14
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Borstlap
V4 Fanatic

Norway
304 Posts

Posted - 08 Jun 2013 :  15:32:57 Show Profile Reply with Quote
The hardware of the whole setup that is V4 specific is not too much, but quite essential. There are of course more roads that lead to Rome, but the one I chose was the most practical one for me; standard materials and a construction that doesn't need welding and is easy to adjust on vital places.

First the big picture and the details afterwards.



















This setup fits within the triangle that is restricted by the fan belt when the mechanical fan is used. When the triangle is reduced because the fan is not used it is more than likely that it won't fit. But than there is quite a lot of room on the front plate that is no longer occupied by the fan and its pulley. On a next engine I intend to use the flywheel as trigger wheel, but that needs extensive work.

Edited by - Borstlap on 08 Jun 2013 16:13:54
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beta
V4 Fanatic

Ireland
278 Posts

Posted - 08 Jun 2013 :  23:29:21 Show Profile Reply with Quote
Thanks for sharing ! Great work !
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beta
V4 Fanatic

Ireland
278 Posts

Posted - 08 Jun 2013 :  23:34:16 Show Profile Reply with Quote
Thanks for sharing ! Great work !
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James Ranaldi
V4 Guru

United Kingdom
1472 Posts

Posted - 09 Jun 2013 :  21:38:06 Show Profile Reply with Quote
Great stuff, very impressive

1968 V4, LHD
1984 99 GL
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x96
V4 Fanatic

Spain
314 Posts

Posted - 15 Jun 2013 :  14:45:10 Show Profile Reply with Quote
This is very interesting. Thank you for your detailed explanation and pictures.

At this point, I imagine it would be easy to fit a single point injection, those early injection similar to a carb, but I see that the direction of the mod is performance instead of fuel consumption.
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Borstlap
V4 Fanatic

Norway
304 Posts

Posted - 15 Jun 2013 :  20:33:31 Show Profile Reply with Quote
Don't these systems require a high pressure fuel pump? Speaking of fuel injection, then I would opt for Megasquirt, then it is also possible to program the fuel supply. Uses the same 36-1 trigger wheel and Edis-module, but Megasquirt is a good deal more expensive than MJ.

Alex
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x96
V4 Fanatic

Spain
314 Posts

Posted - 17 Jun 2013 :  19:24:13 Show Profile Reply with Quote
Yes, the fuel pump of that injections goes in the tank. Surely is high pressure.
The idea came thinking about modern cars similar to 96 in engine capacity, a bit more heavy but with 5 speed transmision (both weight and transmission could compensate) can increase the fuel consumption from 8liters/100km (35MPG) to 6liters/100km (47MPG) thanks to the fuel injection.
That improvment is not too much and the transformation a bit complex. but the engine could run smoother.
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Borstlap
V4 Fanatic

Norway
304 Posts

Posted - 04 May 2014 :  11:08:58 Show Profile Reply with Quote
Time for an update. I have done some changes to the timing settings and run the car now with this setup:



The 600rpm range was of no use, so I dumped it and added a 5500rpm range.This gives a better response at higher revs when flooring the throttle during acceleration.

Last year I started to revive the 96 that has been standing idle for far too many years. First job was to change the worn FoMoCo carb to the Weber DGV I bought years ago. Now it starts without hesitation again. However, it still left room for improvement on the ignition side so I decided to go Megajolt here as well. As I wanted to convert to an electric cooling fan I had to reposition the trigger wheel sensor; the changed pattern of the fanbelt makes this necessary. Finally, in order to get rid of the problem of finding a long enough bolt for the balance shaft pulley I chose for a trigger wheel with a larger centre hole, so that the big washer can get trough. The pulley-triggerwheel combo now looks like this:



Biggest problem is getting a good centration of the trigger wheel. This was done at the workshop at work where they have the proper equipment. Drilling holes connected to my feeble attempts to do this myself at home are stille visible . The arrow points at the TDC marking, the blackened tooth is where the sensor must be.

After I managed to get the cooling fan bearing out unharmed I filled up the hole with metal repair putty and screwed on a bracket for the trigger wheel sensor:



The bracket itself was a piece of predrilled profile I picked up at the local hardware store, nothing special:



In order to get it secured as tight as possible I screwed in bolts from the backside of the front plate with a smear of thread lock to secure that they won't screw loose and end up in the oil sump:



The screws are M6, mut M5 will do. It will make screwing down the various parts easier when the four bolts are a bit further out, but I worked with what I had lying in order to keep work and cost down.

With everything in place it looks like this:



Detail of how the sensor is bolted in place:



Yesterday I had a first start with the Megajolt connected to the test rig with spark plugs; then you can see whether you get a spark or not. An earlier attempt failed due to a faulty ground in the Edis-connector. Yesterday, after rectifying the problem the plugs sparked up . A test with a timing light showed that the trigger wheel sensor is exactly where it should be; no need for correction.

Last thing to do before a real live test is to make a proper vacuum point in the inlet manifold. I just ordered aluminium tube of 3 and 4mm diameter, so this will hopefully be on next weekends to-do list.

Alex
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Borstlap
V4 Fanatic

Norway
304 Posts

Posted - 23 May 2014 :  20:27:31 Show Profile Reply with Quote
So last weekend I took the final step and created a vacuum point. As drilling in the manifold is quite a hassle when it is in place I decided to use the intermediate plate with the connections for the brake booster and crank case ventilation. To get things in place the first thing to do is to remove the centre:



Four mm aluminium tube does the trick; a good deal softer than brass tube, but as it doesn't bear any weight that is no problem. It is also much easier to bend. Because I don't have a drill standard I had to drill handheld, resulting in ending up a bit too high:



Next was fixating the tube and sealing on the outside by using low-temperature melting Techno Weld. On the inside where I drilled through the vacuum channel I dripped in a few drops of thread sealant:



Finally it was closing up the underside of the tube by pincing it down and making two airslits:



Then it was time to get everthing in place again and have a test run using the dizzy for checking if the vacuum was working and getting the engine warmed up. All was well so then came the big moment of changing the spark plug leads. No fun doing that on cylinder 1 when the engine is warm ; the Edis leads meant for use on a Ford Escort or Fiesta don't have a 90 degrees cap and have a long rubber sleeve for keeping moist out, making it hard to push it into place on cylinder 1. Last check, all leads connected correctly? No, cylinders 3 and 4 might be wrong. Changing these two and then the first try: no starting and after a few seconds a loud bang . Double check spark plug wiring on the Sonett for reference: the swap on cylinders 3 and 4 was the wrong thing to do . Swapping back again, giving it a go and: bingo . Strong running and idle suddenly 300rpm higher than with the dizzy, so the sparks must be working better.

That was the rambling for now . Next stage is connecting and tuning the cooling fluid temp sensor for extra advance during cold startup.

Alex
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Borstlap
V4 Fanatic

Norway
304 Posts

Posted - 07 Jun 2014 :  09:27:49 Show Profile Reply with Quote
Slow but steady progress since the last posting. The coolant temp sensor is hooked up and calibrated. After that it was also possible to dial in extra advance and retard based on the temperature of the coolant fluid. A short video clip to show the final result (warning: put the sound down, the audio recording was horrible ):

http://youtu.be/_IfKgYiMd7A

As I wasn't sure how the MJ would influence the reading of the temperature gauge in the dashboard I started by separating them with diodes. This had an effect on the dashboard gauge so I removed it in that line. As the MJ ouput is 5 volts I kept it there for security; would be a bit dumb to blow it up with the 12 volts coming from the dashboard gauge.

Alex
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James Ranaldi
V4 Guru

United Kingdom
1472 Posts

Posted - 08 Jun 2014 :  21:44:04 Show Profile Reply with Quote
Great stuff Alex. Unfortunately I can't make much of the video.

Huge file so my I pad may not be happy.

I can't run the video

Cheers

James

1968 V4, LHD
1984 99 GL
1992 900i Convertible
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Borstlap
V4 Fanatic

Norway
304 Posts

Posted - 08 Jun 2014 :  22:50:52 Show Profile Reply with Quote
I thought Youtube videos were streamed and that there was no inbetween storage, but I am not too familiar with the technicalities. What it shows is that the Aux gauge is rising up to a normal operating temperature and that the cooling fan is switched on and off by the MJ. In addition ignition timing below normal operating temperature is advanced (at start +2 degrees, then +1 en finally 0) and retarded when temperature rises above normal. The fan kicks in when the needle of the dashboard gauge only goes slightly over N, so overheating is dealt with at an early stage.

Today I connected the MJ in the Sonett to the temp sensor. First hookup was a no-no. I had connected to the wire of the oil pressure sensor ; after the meltdown I had in 2006 I replaced a good deal of the wiring and as I was short for brown wire I used a lenght of yellow. I assumed that the 3 on the insulation was an 8 that had lost some of its ink, so I hooked into it. Of course the correct wire was well hidden, so it took an hour or so to correct matters. But the test drive showed good results, so I am a happy man .

Alex
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James Ranaldi
V4 Guru

United Kingdom
1472 Posts

Posted - 09 Jun 2014 :  10:32:20 Show Profile Reply with Quote
Hi Alex,

Great stuff.

I understand that ignition timing can influence the engine running temperature but I am not clear about using the temperature to change the ignition timing How does this work ?

Does the resulting change to the timing not influence the engine running ?

Cheers

James

1968 V4, LHD
1984 99 GL
1992 900i Convertible
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