New Ignition Coil and Conversion

[gvarney13]

Hello All

I have just recently changed my 1987 Gm 4 cyl 3.0 from conventional ignition to electronic. I also changed out the coil but I need to disconnect the resistor if in fact it has one. Any ideas what to disconnect?

Thanks

Guy

 

[Haut Medoc]

Re: New Ignition Coil and Conversion

Some have external resistors which is actually the wire that feeds it....
Some have internal resitors.....
What does your old coil say on it?.....​

 

[gvarney13]

Re: New Ignition Coil and Conversion

The old Coil has "Use with External Resistor" stamped on it...

 

[Don S]

Re: New Ignition Coil and Conversion

What kind of conversion did you do???? There are several ways to convert, and what to do with the resistor depends on what you now have.

 

[gvarney13]

Re: New Ignition Coil and Conversion

I installed a Pertronics Conversion Kit and a Pertronics Flame Thrower Coil.

 

[thumpar]

Re: New Ignition Coil and Conversion

I just did almost the same conversion but went with the flamethrower II to match the ignitor II. Same setup though.

What I did was remove the + wires from the old coil and tape them up good into the wiring harness. Then I removed some of the tape from the harness that runs along the valve cover and tapped into that for the new coil wire. When done tape it back up like it was.

Works great. I am pulling an extra 300RPM over last year with points.

Just an FYI: If you have the ignitor I make sure you don't leave the key on without the engine running as it will fry the module.

 

[gvarney13]

Re: New Ignition Coil and Conversion

What I did was remove the + wires from the old coil and tape them up good into the wiring harness. Then I removed some of the tape from the harness that runs along the valve cover and tapped into that for the new coil wire.

I am not quite understanding what you are saying. You remove the + wire that goes to the ignition and the slave solinoid and left the + wire from the Ignitor?

Guy

 

[thumpar]

Re: New Ignition Coil and Conversion

I originally had 2 wires going to the coil. 1 from the starter and 1 resistor wire. I removed them both and taped them up incase they need to be used in the future. I then removed the tape from the harness just inches from the coil and tapped in to the purple wire. Ran it to the + on the new coil and hooked the ignitor + wire to the coil + also.

The wire that runs from the starter is a kickup to true battery voltage while cranking the starter, which is not needed anymore. The other wire is the resistor wire and drops the voltage so we don't want that either. That is why you tap into the true battery voltage purple wire.

 

[gvarney13]

Re: New Ignition Coil and Conversion

Thanks

Know I understand. I am going to rework wiring this weekend.

Guy

 

[Scaaty]

Re: New Ignition Coil and Conversion

Jeez...new coil means no resistor if Pertronix. Just find out where your Ballast Resistor is...bypass and connect ..thats ALL. This BS of messing with wires on the coil is ludicrous as whats there will work just fine

 

[thumpar]

Re: New Ignition Coil and Conversion

Jeez...new coil means no resistor if Pertronix. Just find out where your Ballast Resistor is...bypass and connect ..thats ALL. This BS of messing with wires on the coil is ludicrous as whats there will work just fine

The resistor is the wire. It can't be use because of that.

 

[Scaaty]

Re: New Ignition Coil and Conversion

The resistor is the wire. It can't be use because of that.

Then just replace it with a new wire of appropriate gage. You can leave everything else alone.
Ya need that wire as thats the feed after start..9v with points, but now you need the full 12+ with Pertronix. You have another 12V wire that comes off the starting system to the coil, but it can be left alone.

 

[thumpar]

Re: New Ignition Coil and Conversion

The reason I didn't just replace the wire is because it is in the harness that goes from the coil to and around to the other side of the motor. It is all taped up and I didn't want to remove more than I had to. So I just tapped into the closest 12v ignition that I found (the purple wire in the harness next to the coil).

When I tapped in I split the insulation, be careful not to cut the wire. Spread it open a bit and soldered the wire in. Put a good end on and done.

 

[hoot]

Re: New Ignition Coil and Conversion

gvarney, i did the same as you, converted to electroic. you need 12v at the coil post all the time while running. the pertronix coil has an internal resistor. i pulled my key switch and found the run terminal with 12v on it with the key in the on position. i ran a wire from that terminal back to the coil post. i also determined which wire was the resistor wire and removed it from the coil post and taped up the end.

 

[Magik]

Re: New Ignition Coil and Conversion

what are the benefits for this mod other than extra hp?

btw whats is an expected hp gain for the 4 cyl?

thanks

thomas

 

[thumpar]

Re: New Ignition Coil and Conversion

what are the benefits for this mod other than extra hp?

btw whats is an expected hp gain for the 4 cyl?

thanks

thomas

It is not so much as hp as it is more accurate and you don't have to change/adjust points ever again. I did gain about 300RPM over what I had though. It starts much easier too.

 

[hoot]

Re: New Ignition Coil and Conversion

i don't think you get any hp gain. i have an inline 6 and it seems to idle smoother and run smoother at any rpm. doesn't start any quicker or easier. with the petronix internal resistor coil, it also eliminates the resistor wire that cuts volts to the coil.