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Dual ballast primary resistance value?

Ron_M

Ron_M

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On the dual ballast primary side, the published good resistance value is 0.5 to 0.6 Ohms.
I have two used ones that measure 1.1 and 1.2 ohms. Are these considered "good"?
I compared to an NOS piece, that measured 1.3.
All measurements made at room temp.
Thanks in advance.
 
Ron_M said:
On the dual ballast primary side, the published good resistance value is 0.5 to 0.6 Ohms.
I have two used ones that measure 1.1 and 1.2 ohms. Are these considered "good"?
I compared to an NOS piece, that measured 1.3.
All measurements made at room temp.
Thanks in advance.
Click to expand...
The BEST SOURCE for ignition system information is @HALLIFAXHOPS, a supplier on this site .....email him...he can also supply NOS and after market parts.....distributor parts, coil, ECM MODULES, caps, rotor etc.......a good person to know......just my opinion of course......
BOB RENTON
 
Thank you.thats where I got most of these though.
 
Somewhere I read it in Chrys literature: 0.5 & 5 ohms for the dual res.
 
Also test them hot/warm the ohm values drop. There are alot of different single ballast values out there from .25 usually .5 -.6 is 95% of the single points. ECU's should be matched.

ecu chart 2.png


ecu III.png


ecuII.jpg
 
Duel ballast is 5 ohms on the run side and 1.2 on the start side if thats whart you need?
 
Mmmm wait, I think the info is being mixed.

the OP is asking about its double ballast primary resistor value, which it’s on its primary resistor on 1.1-1.3 ohms rate per his measurements while the books says should be 0.5 ohms

I have also found both primary measurements on market for the double… 0.5 and 1.2 ohms. Both measured cold.

wondering why if books state 0.5 there are also 1.2 available.
 
The one I posted are the Mopar oem. Aftermarket are all over the place from what I have seen. Also I noticed room temp measurements are a bit high. I hit them fast with a heat gun like they would be operating and they drop into tolerance, usually.
 
Just from testing different ecu's and ballast values, they really make a difference on RPM. Say the ecu is a real Chrome one 10K rpm and it is supposed to use a .25 ohm ballast it will go to 10K, but heats up the ecu fast hence strip only. Now put a 1 ohm ballast on it it will hit say 7K rpm and stay cool and you can use it on the street but will not get 10K out of it.
 
It's not the resistors. It's the car itself. There's a member on FABO who posted some things to try in a post with another FABO member this summer that's really good. I need to do that.
I'll PM ya Ray tomorrow.
 
Same Mopar Chrysler Part # on both

They changed resistance at some point in the mid to late 70s like stated from .5 to 1.2 OHM

OHM resistance is stamped inside male blades

Peace

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IMG_1452.jpeg


IMG_1451.jpeg


IMG_1449.jpeg


IMG_1447.jpeg


IMG_1446.jpeg
 
Bee1971 said:
Same Mopar Chrysler Part # on both

They changed resistance at some point in the mid to late 70s like stated from .5 to 1.2 OHM

OHM resistance is stamped inside male blades

Peace

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Click to expand...
IMO....the "best ones" is the one with the exposed resistor element as the totally enclosed units tend to over heat, especially the resistor that controls the coils primary current either the 1.2 ohm or the original 0.5 ohm value. The totally enclosed units will fail significantly quicker than the open back unit. And they fail without prior warning....keep a spare in the glove box.....just my opinion of course....
BOB RENTON
 
I disagree with post #18. It costs more to enclose the bal res elements compared to leaving them open. Why was the extra money spent if it did nothing?
When the res fail, it from the wire breaking; the wire becomes brittle over time from constant heat/cooling cycles. Sometimes the former that the wire is wound on breaks because it too is brittle.
So I believe encasing the res wire is a good idea. It keeps the wire supported & free from vibration.
 
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