How can I disable direct coil control?

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usagoal
Helpful Squirter
Posts: 40
Joined: Fri Nov 19, 2004 5:27 am
Location: new jersey

How can I disable direct coil control?

Post by usagoal »

Here is my current ignition setup: Direct coil control. Tach input signal provided by a Pertronix unit + pull up resistor using step 50a from the V3 assembly guide.
I would like to disable direct coil control and return my ignition setup using the Pertronix unit to trigger the coil's negative terminal (as it was originally designed for). My questions are:

1. Can I use the Pertronix to both trigger the coil negative AND provide a digital signal (using the pull up resistor) while still using step 50a (hall/optical input circuit)? Does anybody disagree with this?

2. Can I disable the direct coil control circuit by removing the jumpers from IGBTIN to JS10 and IGBTOUT to IGN? Or must I remove the other components in the circuit?

As with both questions, I'm trying to keep the soldering/resoldering to a minimal and only change a few wires around under the hood to complete the switch from direct coil control to old school distributor controled ignition. any help is appreciated. Thanks.
1962 Buick Skylark 215 V8
Bored and stroked to 266, Port Injection, Pertronix ignition AEM WB 02
1977 28' Mercruiser 351Windsor, TBI, Pertronix ignition, NB o2
Both MS-II 2.891 , V-3 board
trakkies
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Posts: 1162
Joined: Tue Dec 30, 2008 3:06 am
Location: SW London, UK

Re: How can I disable direct coil control?

Post by trakkies »

Presumably you have to reinstate the wiring between the Petronix and coil, so why not just extend the MS ignition input to the coil negative as per the MegaManual? Personally I'd not use the extra MS input circuitry for a sensor if not actually needed, since a direct input from the coil exists.

I fitted veropins to the MS PCB to allow easier removal/replacment of links.
Dave P, London UK.
Rover V-8
MSII V3
EDIS
Tech Edge Wideband
usagoal
Helpful Squirter
Posts: 40
Joined: Fri Nov 19, 2004 5:27 am
Location: new jersey

Re: How can I disable direct coil control?

Post by usagoal »

I will be going to coil negative, I'm just trying to get away with using the already installed pull up resistor and MS ignition input (hall/optical sensor) that I had already soldered in during the MS build. I'm trying to avoid having to remove components and switch my MS input to the other circuit type (coil negative). I know it's only a few components I have to solder on the board but eventually I may go back to direct coil control. If I have to, I will remove the wiring & resolder, but I thought I could cheat a little! :)
1962 Buick Skylark 215 V8
Bored and stroked to 266, Port Injection, Pertronix ignition AEM WB 02
1977 28' Mercruiser 351Windsor, TBI, Pertronix ignition, NB o2
Both MS-II 2.891 , V-3 board
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