ballast resistor do you need it??

[The Mechanic]

Hey guys and gals,

I have a 1967 Dodge Polara with a built 383, it has mopar electronic ignition (blue box) and Holley sniper 2 fuel injection, Holley sniper coil, and internally regulated alternator. With all that said, my engine builder said by having the ballast resistor in line I am limiting the voltage to the coil. He said the Holley coil can handle 12.7 volts constant and that I should bypass the ballast resistor to give the coil full power. I have not tried this yet. I thought I would bounce it off of the Mopar gurus here on this site and see what sticks. Please let me know if you think this will work and will it be safe.

Thanks Keith

 

[Badvert65]

I think you would be better served checking with the maker of the coil.
jus sayin

 

[MoPar~Man]

Does the sniper fuel injection system not also come with an ignition module?

There are coils that have internal resistors. And I guess it is common that aftermarket coils will come with an external ballast resistor if they need it. Some say that the ballast resistor is contained in harness wiring. What is the exact model / part number of the sniper coil?

Remember that your coil will be seeing 14 to 15 volts when the engine is running, not 12.7 volts. Not having the resistor can make the coil unhappy, and certainly raise it's temperature. The ballast resistor is normally bypassed during engine start, this is done at the ignition key switch.

 

[CBODY67]

As the type of the ignition system is an integral part of any EFI system, I would also suggest that the instruction sheet for your Holley system should ALSO be consulted. To VERIFY what the local person is saying, accurate or not.

On many EFI systems, they use the ignition distributor to gauge engine rpm levels, so accuracy is important. Along with a solid, non-interferred-with voltage supply, which can mean a high-quality solid state voltage regulator rather than not.

CBODY67

 

[The Mechanic]

The sniper system did not come with an ignition module, there were several options from Holley but I already had the Mopar system in place, I just checked on the holley website and it says the coil needs a ballast resistor if your using points, ( Holley part number of the coil 556-153) so I would say the coil is made to handle full battery power. So now I guess my next question becomes is it safe for the rest of the system to bypass the ballast resistor?

 

[halifaxhops]

Really depends on the way it is wired. Which blue box? Mopar or aftermarket also?

 

[MoPar~Man]

Do you have a good volt/ohm meter? I'm curious what the primary winding resistance is of your coil.

 

[The Mechanic]

Ray, I think the blue box is mopar, but I am running an internally regulated alternator so I have no wires going to the regulator from the alternator, the rest of the wiring is stock.

 

[halifaxhops]

Any chance you have a picture of the top of it? Common color on NORS also.

 

[halifaxhops]

I would run a ballast. Most boxes need a ballast or they heat up and cook internally. Here is just a chart of recomended ballast to box.

 

[The Mechanic]

I dont have a picture of it right now, these charts are interesting! I will have to check on the part number of my ballast resistor, Im sure its been replaced, I was thinking that running a ballast resistor was probably a good idea. Thanks for all the input!!

 

[413]

How does the car run, do you need to change anything?

The 5 pin ignition box needs a ballast, 4 does not.
Contact Holley with the coil part number and see if it can handle 15 volts constantly.

 

[The Mechanic]

The engine doesnt idle well, seems rough to me, and it sometimes falls on its face while ringing out the gears, I feel the stumble at higher rpm is in the ignition somewhere, but its hard to tell. I will contact Holley and see what their coil can handle but Im still leaning towards keeping the ballast resistor. How do I know which ballast resistor is correct?

 

[413]

Is your blue box 5 pin or 4 pin? Is your ballast a single or dual? 2 terminals or 4 terminals. The ignition wiring was addd on to your 67, where is it connected to the car wiring to get power?

 

[The Mechanic]

Blue box is a 4 pin, single ballast resistor, I think it gets its power from the ignition switch, or the adjoining wire that goes from the ballast resistor to the ignition switch, Im not near the car currently so Im going by memory.

 

[RemCharger]

The ign box wants a ballast resistor or will burn out , as stated. If you want to eliminate it, get an msd.

 

[The Mechanic]

So an MSD will not be effected by bypassing the ballast resistor? I never knew that! I actually have an MSD somewhere in my stash of car parts. That might be the way to go, especially since the car stutters sometimes during hard acceleration and idles rough. Thanks for the info!! I just love this website!! There is so much knowledge out there that people are willing to share. Thanks to all who chimed in on this subject.

 

[413]

A 4 pin Chrysler ignition box has a 12+ wire
a wire to coil -
2 to the distributor.

No ballast needed.

 

[The Mechanic]

Im sorry, I dont follow what your saying, yes 2 wires to the distributor, 1 wire to the coil, and what do you mean a 12+ wire?

 

[RemCharger]

A 4 pin Chrysler ignition box has a 12+ wire
a wire to coil -
2 to the distributor.

No ballast needed.

I completely disagree.