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ballasted system

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Usually refers to the ignition coil, basically, a non-ballast coil is designed to produce full spark output with 12 volts on the input (+ terminal). A ballast coil is designed to produce the same spark output, but with only 6 to 9 volts on the input.

Anyone else??
Ɛan
 
Barry, bugeyes are not balisted. We are pureists.
 
Ballast is resistance in series with the ignition coil primary. Sometimes it's a separate resistor, sometimes a length of resistive wire, and sometimes the coil is made so it has enough resistance by itself (called an "internally ballasted" coil). Without some resistance somewhere, you get too much current in the coil and it will actually get quite hot, even burn out.

The separate resistor, if you have one, is usually a ceramic brick about 3" long. If the coil is "internally ballasted" it will measure something like 3 to 4 ohms and there will be no external ballast resistor.

Electronic ignitions are specifically designed to work with or without ballast. For example, the Crane XR700, which I use, requires either a ballasted coil or external resistor. The Crane XR3000, however, specifically must not have ballast resistance. So, if you install an electronic ignition, you need to be sure you have the right kind of coil.
 
Yeah and without the ballast resistor in there engine will run like a scalded dog so much pep and power. Unfortunately the coli overheats and fairly quickly burns up. Speaking from experience when the Mercruiser mechannic left off a minor part, $2.00 ballast resistor, and I replaced 5 coils before the problem was identified. And we won't talk about getting stranded in the middle of the lake and needed to be towed in 4 times. Idiot boat mechanics. Don't get me started on that topic.
 
But it is nice to get a hot spark on start-up with a ballast resistor system. I have one on my Sprite and the coil gets 12 volts on start-up (jumper from starter solenoid straight to the coil, WITH DIODE!!!) and then the reduced (proper) voltage to the coil during running. Honda resistor block and Shuck's cheapest ballast type coil. Works great.
Bill
 
So I was looking at the flame thrower coil. What differences would be expected? Is it worth the purchase? I do have a petronix dizzy.
 
I wasn't aware that Spridget use a ballast resistor. Barry, the differences in performance I experienced with our SeaRay were incredible. I could put the hammer down and Colleen would pop out of the water like a cork. No lollygagging while boat built speed to get her to plane out on one ski. She was up right now. Now the unfortunate part was that as afternoon went on and coil started to heat up/overheat things would start getting really flaky. Not sure what the long term effect would be of keeping straight 12 volts rather than a ballast resistor in the system but it sure makes the engine easier to start. Getting stuck after dark however and needing to get towed in was a definite disadvantage.
 
Well, the reason that I am asking is because of the two different coils that are available. I am looking at the flame thrower coil to go along with the petronix unit that is installed. There are two different coils listed. One for a ballasted system and one for non-ballasted.

I just wonder what kind of performance difference I can expect between a stock coil and the flame thrower. The name sure sounds "fast". :smile:
 
Jim
The Spridget (at least the 948-1275 version) NEVER came stock with a resistor in the system. It is only there if we shade-tree mechanics put them there.

Barry
You need to find the literature for the Pertronix to find out if you need ballasted or non-ballasted.

Bill
 
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