Pertronix Ignitor install on 2.7 conversion, couple of questions... Options

[Ferg]

So two things I need to find out to finish this install...

1. What is a good switched 12v power source for the red wire? One that is close by the distributor and coil?

2. I took my bosh coil off, to test ohms and only got .6, the instructions say i need 1.5 ohms so I think i need a new coil. what kind? Oil or epoxy, Is pertronix flamethrower coil the way to go?


Thanks Ferg.

[lapuwali]

If you only have 0.6 ohms across the side posts of the coil, you probably have a ballast resistor in the system somewhere. Either an actual resistor block itself (usually near the coil), or a high-resistance length of wire. This would be hooked up between the switch and the coil + terminal. The Ignitor directions should detail all of this for you. The normal place to hook the red wire on the Pertronix is the + terminal of the coil itself, which has switched power leading to it. However, if you do have a ballast resistor, you need to hook up the Pertronix on the switch side of that resistor, rather than the coil side of the resistor.

[Ferg]

I am sorta following you, but very electrical stupid, so bear with me... when I tested the coil I took it completely off the car, and tested with no wires whatsoever hooked to it, so the resistor (if i have one) should have no effect on my reading of .6 right???

Ferg.

[lapuwali]

Coils are either internally or externally "ballasted". Either the resistance is in the coil itself (true for the typical "Bosch Blue", for example), or is an external resistor. If your coil only measures 0.6 ohms with no external wires attached, it's not internally ballasted. If it were, you would see 1.5 ohms or more across the side posts (probably something like 3 ohms). Since there's no internal ballast, there's probably an external one, either an actual resistor, or just a high-resistance wire. Either of these will be between the + post on the coil and whatever it connects to (eventually, it will reach the ignition switch, but it probably hits a fuse first, and may hit some internal connector first).

If there's no obvious box there (ballast resistors are large) connected to the coil, then it's probably in the wire itself. Try tracing that wire to it's other end, and measure the resistance across it. If there is very little resistance (that is, if the resistance in the wire/resistor and the coil both add up to less than 1.5ohms), then your ignition system has no ballast at all. If so, you'll either need to get an internally ballasted coil, or an external ballast resistor. If there IS enough resistance through that wire, then you need to hook up the Pertronix red wire to the far end (not the coil end) of that wire.

[Ferg]

Cool, that makes sense. i'll hold off on buying a new coil and test/check to see about the resistor.

Ferg.