[jmplaysbass]

Hi all
So I replaced my points with an ignitor module, followed the instructions (or what there are of them), and since I installed it I havn't been able to get the engine to fire. I tried wiring it directly to the coil (3.5ohm), then to the orignal harness, neither worked, buzzed the line out, all have continuity. Has anyone had any luck installing these things/did any of you have to modify the module mounts?

 

[Alfar7]

Distributor

Did you re-set the ignition timing?

 

[144]

I installed a Petronix Igniter in my 74 Spider about 15 years ago and it's been working flawlessly . . . much better and more reliable than the points.

In your '78, you should have a dual point Marelli instead of my single point. On mine, I did have to elongate a couple of holes in the Petronix mounting plate to get the pickup close to the cam lobe. Otherwise, very simple, time the engine to TDC of power stroke and index the distributor and plug wires accordingly. That should allow the engine to start and run, where you can then put a timing light on it and fine tune the ignition timing.

 

[Alfajay]

Did you re-set the ignition timing?

Is your problem:

1) That the timing is now incorrect, as Alfar7 asks.

OR

2) That the coil isn't putting out a spark?

Connecting a timing light to the coil-distributor lead and then cranking the engine will answer this. If the timing light fires, then you have spark and timing is probably the issue.

If no spark, then perhaps the Pertronix module is too far from the cam lobes as Roadtrip suggests. Once you get that sorted out and have evidence of a spark, you will still need to set the timing.

 

[alfaparticle]

Jay's advice is good. The upside of these things is that they are more reliable than points. The downside is that it is impossible to set the static timing accurately.

 

[Alfar7]

Timing

The only timing that matters is the max advance.

Turn the distributor until it starts. Set max advance (32 degrees typically) and the static will be where it is. Marelli distributors have a weak spring issue, that effects idle speed as the springs don`t return the counter weights to there resting point.

Clean the weights rub surfaces and change out the spring with the long "U" hook to one of the shorter versions on the other counter weight.

 

[alfaparticle]

My 2L with 10.5 pistons needed 34 degrees to make maximum power. It was few HP down at 32.

 

[jmplaysbass]

I think the module it's self is too far from the lobe, the mounting points are almost drilled through the outside of the plate. I tried the other day setting the timing ranging +/- 40 degrees from where it was set with points and nothing

 

[alfaparticle]

Remove the wire from the coil -ve that goes to the module and connect a voltmeter between that wire and ground and turn the distributor. You should see the voltage switch from 0 volts to 12 volts if the module is working.

 

[jmplaysbass]

thanks everyone for the suggestions, Roadtrip hit the nail on the head, the factory mounting holes were miss-drilled, rebored the holes, set the spacing, and my alfa fired right up

 

[chamois]

wiring with ballast resistor

Just got one of these Pertronix kits from C-line for my 72 GTV. Did you guys wire through the ballast resistor or go directly to the coil terminals? Thanks

 

[alfaparticle]

I have no experience with Pertronix but assuming that it functions similarly to a 123ignition distributor:
+12V goes to the hot side of the module (probably red wire) and to the ballast resistor.
Coil positive goes to the other side of the ballast resistor.
The low side of the module (probably black wire) goes to coil negative.