ballast resistors

70Tom

70Tom

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As it was brought up in another thread, I figure I should ask. Currently, the ballast resistor is bypassed on my car. I'm not sure why the previous owner did this, but it is. Should I leave it as it is, or reconnect back to the ballast resistor? I'd rather not have any issues down the road because of a stupid fix to something.
 
70Tom said:
As it was brought up in another thread, I figure I should ask. Currently, the ballast resistor is bypassed on my car. I'm not sure why the previous owner did this, but it is. Should I leave it as it is, or reconnect back to the ballast resistor? I'd rather not have any issues down the road because of a stupid fix to something.
Click to expand...
People bypass them when running newer style coils that require the full 12v. If you're running a stock coil, you should get it back online.
 
Ah, ok, that makes sense. I think it is running a newer style coil, so this would be appropriate. Appreciate the help.
 
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thanks Tom!

I am running a summitracing knock off Chrysler electronic ignition and am having problems with the engine running smoothly. The instructions for the ignition kit show a ballast resistor in the wiring and I have wired it up that way. The comment above about a "newer style coil" was making me thing maybe I don't need the ballast resistor...but now am pretty sure I do.

Dave
 
dmac01 said:
thanks Tom!

I am running a summitracing knock off Chrysler electronic ignition and am having problems with the engine running smoothly. The instructions for the ignition kit show a ballast resistor in the wiring and I have wired it up that way. The comment above about a "newer style coil" was making me thing maybe I don't need the ballast resistor...but now am pretty sure I do.

Dave
Click to expand...
Sorry, I was only partially correct above (now edited). If you're running the MSD ignition, you don't need the 12V wire. If running points/stock distributor, you do. However, as you can see in the image, you still need the ballast resistor.
 
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So based on the instructions for Dave's coil above, a) it is considered a new style coil and it requires a 12V source if not using the MSD ignition, and b) it still uses the ballast resistor. So what is the theory/thought on this? Is bypassing the resistor just a way to get around having a direct 12V source from the battery?
 
70Tom said:
So based on the instructions for Dave's coil above, a) it is considered a new style coil and it requires a 12V source if not using the MSD ignition, and b) it still uses the ballast resistor. So what is the theory/thought on this? Is bypassing the resistor just a way to get around having a direct 12V source from the battery?
Click to expand...
Slight oversimplification... when cars changed from 6 volts to 12... the ignition wasn't a problem. 6 volt coils lasted a long time after. The resistor is to cut the operating voltage to something the coil can survive.

Once the 12 volt coils and their additional energy potential got popular, fewer cars had ballast resistors.
 
cantflip said:
Slight oversimplification... when cars changed from 6 volts to 12... the ignition wasn't a problem. 6 volt coils lasted a long time after. The resistor is to cut the operating voltage to something the coil can survive.

Once the 12 volt coils and their additional energy potential got popular, fewer cars had ballast resistors.
Click to expand...
Gotcha. Thanks for the clarity. I'm new to this electrical thing. :wideyed:
 
70Tom said:
Gotcha. Thanks for the clarity. I'm new to this electrical thing. :wideyed:
Click to expand...
You'll be fine... always lots of good help in here. @Big_John puts up a ton of great information to help anyone. I've chilled a little, but will chime in when I think I can do good vs make something more confusing.
 
Ballast resistor and resistor wires( GM) are because the coil is designed to operate at 9volts which is what the battery voltage drops to when cranking starter motor. When car starts the system voltage goes back to 12 volts so the ballast resistor or resistor wire is used to cut the voltage back to the 9 volts the coil was designed to operate at causing it to operate normally instead of overheat from over voltage.
If your car is basically stock, a 12 volts coil that is still rated at 40,000 volts is not going to make your car faster. No fouled plugs, no ignition miss that's it, it is doing its job and your car is not going to lose a second on your 0-60 time because you have 3 more volts going into the primary side of the ignition coil.
Stop reinventing the wheel they work best when round.
 
99% of the items in a SummitJegs catalog are best for dedicated track cars.
99% of the items in a SummitJegs catalog end up in street cars that go to Dairy Queen on Friday night.

What a racket....
 
commando1 said:
99% of the items in a SummitJegs catalog are best for dedicated track cars.
99% of the items in a SummitJegs catalog end up in street cars that go to Dairy Queen on Friday night.

What a racket....
Click to expand...
And of course after someone screws up their car, we get to fix it back.
 
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