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Discussion Starter #1
Good day

Got hold of a 123 ignition for my 2 liter Bertone and am a bit puzzled abt static advance setting. The installation manual tells me to bring the car on the static marks on the pulley and then install the dizzy and turn it until the green led light up. Is that all ? Is the static advance then memorized in the choosen curve or do have, once installed, play with the dizzy and strobo light to get the advance i want/need at 1000 rpm ?

Car have head ported, bigger valvs, Alfaholics RCE4009 cams, skimmd head, dell'orto 45 etc. HC piston etc etc.

Many tks for your kind help on this

Best,
Gianni
 

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If you have the version with 16 switch selected curves then you must mark the pulley for the static timing of the curve that you select.
If you have the Bluetooth version then the procedure is different and it has been documented on the ABB by Gubi and others.
 

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Discussion Starter #3
Good day Alfaparticle,

and may tks yrs. Have the version with 16 cuRves (0 to F). Have a fully marked pulley every 2 degrees all along the circumference. Let me understand better. Assuming would like to have the curve D, and would like to have 13 degree static, once curve selected and car started have then to set the dizzy to read 13 degr on the pulley at idle correct ?
 

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I have the same 123 distributor.

My understanding is, as you say, you fit the dizzy with the engine set to your chosen static timing. In your case you mention 13 degrees before TDC. That's it. With curve D selected, you will then get 21 degrees of speed advance from 1000 to 4000 rpm. You can check the timing with a strobe light at idle and 4000rpm to confirm.

The static timing is locked in by how you fit it. The speed advance comes from the curve you select (microswitch position)
 

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I agree. Set the engine at 13 degrees BTDC and follow the instructions about rotating the distributor and watching the LED and as Malcolm suggests check it again at high rpm the verify that it is at 34 degrees, I would do that at 5000 rpm in case your tach is reading high.
 

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Discussion Starter #6
Many Tks Guys.

Since the dizzy is connected to an MSD 6AL module do not get the led to light so have set the dizzy 'more or less' started the engine and then properly set it at 13 deg at idle (1000 rpm) with the strobo.

Do appreciate yr help on this.


Best,
Gianni
 

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Here are some words of caution regarding use of an MSD or other CD ignition with a 123 distributor.

I used the 123/ MSD 6AL combination for a number of years and I was happy with it until things started to fail. First, the distributor cap, rotor, then the plug wires, then the cap and rotor again and then the 123 failed.
The cap, rotor and wires failed because of the repeated high voltage pulses from the multi-spark.
I sent the 123 distributor to the importer for repair and it needed a new PCB. They sent me a picture of burned up components on the old board and they said that they had a few similar failures on distributors that were firing CD units.
I removed the MSD 6AL and installed an MSD Blaster coil with an MSD ballast resistor and it works very well on a high rpm, high power motor. Also my timing light works better with the inductive system, particularly in the rpm range where the 6AL is making multiple sparks. I have posted about this in other threads and I have included coil current curves that show the superiority of this setup to some other inductive options.
 

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Discussion Starter #8 (Edited)
Tks for the hint. Have been using the MSD since many years and worked just fine althought with a normal dizzy and pertronix. Will try and run the coil alone and see how the car runs. Will have an issue by dismissing the MSD since use its tach output to drive the rev counter....
 

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The tach signal output is the only part of the MSD that I miss. My car tach runs fine from the -ve terminal of the coil but it is not clean enough for my Zeitronix data logger. It would be nice if my 123 had a tach out signal.

I suggest that you wire in a high watt resistor of about 3 ohms in parallel with the input to the MSD if you decide to keep it.
 

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That's why I really like the BlueTooth version. Set the green light to light at TDC and program in any advance you want at any speed including idle.
 

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Discussion Starter #11
The tach signal output is the only part of the MSD that I miss. My car tach runs fine from the -ve terminal of the coil but it is not clean enough for my Zeitronix data logger. It would be nice if my 123 had a tach out signal.

I suggest that you wire in a high watt resistor of about 3 ohms in parallel with the input to the MSD if you decide to keep it.
Tks. Resistor in parallel to msd input or output ? Sorry for the stupid question but never ever used ballast resistor before.
 

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The 123 distributor, like the Bosch ignition modules, tries to control the coil current. But it cannot "see" the coil current when it is hooked up to an MSD which has a much higher input resistance. I think the failure mode of the 123/MSD is related to that. So I suggest installing something that looks like a coil to the 123 in the place where a coil would normally be - between the black wire of the 123 and + 12V. It should be about the same resistance as the coil and must be suitable wattage. 50W is a safe number. Maybe 25W would be OK.
 

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