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Discussion Starter #3
I did ... I don’t know where the mag pick up or points are on the gtv6... is it the green wire that comes out of the distributor?
 

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81 - 83 GTV6 use a VR pickup and 84 - 86 use a Hall sensor. They have different ignition components. The strobe signal to the L-Jet fuel computer comes from the ignition circuit. You need to think this stuff through.
MSD ignition sends high voltages to the coil that can damage anything else that is connected so check that out, example where is your tach signal sourced?
GTV6's have balanced, carbon filament HT wires that can be damaged by multispark, CD ignitions. I had a Crane ignition on a GTV6 with Megasquirt for a while and it was more trouble than it was worth and I went back to basically stock Bosch. That motor made 260 HP at 7000 rpm.
 

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And according to my wiring diagram I have nothing going to my ignition from the L jet

But your L-Jet is getting a signal from your ignition. You better be sure about that signal level when you modify the ignition so that you don't smoke your L-Jet computer.
 

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Discussion Starter #7
H20 = inertia switch
B1=ignition switch
G1 = fuse box
A1=battery
Could it be connected to the ignition box through the fuse box ?
 

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I think that the strobe signal is on pin 1 of the L-jet computer. I don't remember where it is sourced. I gave all of my technical manuals and diagrams to the guy who bought my GTV6.
 

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Discussion Starter #9
According to my ignition diagram it goes straight from my ignition coil to the L jet ‘s pin 1 through the 2 way connector four oil
 

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Discussion Starter #11
These are the only 3 harnesses disconnected from my L jet. The left side of the combo relay , a green wire which I suppose it’s my o2 sensor and a black connector that might be my ignition wire
 

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On a 1984 GTV6 the pickup is a hall sensor in the distributor. The sensor needs a stabilized 12V source which comes from either the ignition advance computer or the Bosch ignition module, I don't remember which. The Hall signal then goes to the ignition advance computer and then to the ignition module which switches the -ve terminal of the coil to ground to charge the coil and opens to make the spark. If you try to use the Hall signal before it goes to the advance computer to trigger the MSD then you will have fixed advance and the car will be hard to start. You may be able to use the signal from the computer to the ignition module but you must be sure of the phasing. Some devices trigger on the falling edge of the signal and others on the rising edge.
You could leave everything in place but replace the coil with a high power resistor of about 1 ohm and pick off the signal for the MSD but again you must be sure of the phasing. The ignition module varies the dwell angle with rpm and if you use the wrong side of the pulse from the big resistor your ignition timing will be all over the place.
 

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According to my ignition diagram it goes straight from my ignition coil to the L jet ‘s pin 1 through the 2 way connector four oil
If you use that and the coil is fired by MSD then you are likely to smoke the computer. I expect that there is a warning about that in the MSD literature.
 

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Why are you installing the MSD system in the first place? In my experience it is only necessary in modified, high-compression and/or high-boost engines that tend to run on the rich side and foul spark plugs (think air-cooled 911, Nord Alfa 4-cylinder with high-dome pistons). It will probably be more trouble than it is worth on an otherwise stock GTV6, especially if you are retaining the factory L-Jet fuel injection system. Like Ed said, even if it doesn't harm your stock ignition module, it is very hard on spark plug wires and the cap/rotor.
 

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Discussion Starter #15
So story on my car is , I was on the track and it caught fire , all my fuse box melted so I decided to re-do the whole wiring on the car . I have all the lights , blinkers, horn etc working but I just thought it would be easier to run a MSD I had from my old race car. I am redoing the stock harness with the stock ignition module now , gave up with the MSD
 

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So story on my car is , I was on the track and it caught fire , all my fuse box melted so I decided to re-do the whole wiring on the car . I have all the lights , blinkers, horn etc working but I just thought it would be easier to run a MSD I had from my old race car. I am redoing the stock harness with the stock ignition module now , gave up with the MSD
Ed 'Alfaparticle' did give me an entire EdEncyclopedia when I bought his car and I am more than willing to share any info that would help any other Alfist with whatever they need.... If you need anything in particular such as photos or electrical diagrams then I am more than willing to help out in any way I can... I attached one of Ed's dead sea scrolls.... if this doesn't help at all then please let me know and tomorrow I will be working on my car and I can take some photos for you... It should be known... Ed is incredible with his knowledge... I'm probably 5-10 years away from being at 40% of his knowledge... but I'm enjoying the learning curve and I hope I can help share his wealth of knowledge any way I can
1604291
.....🤠
 
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