Ok, here's the deal.

I have a new 1361A pertronix to install. The question is the coil, as I'm in the middle of their recommendations.

Stock Coil is 1.5 Ohms with .6 Ohm ballast

Pertronix has 1.5 Ohm and 3.0 coils.

From various sources I've gotten

4cyl & 6cyl use 3.0 coil, no ballast
8cyl use 1.5 coil, no ballast

4 cyl, max amp draw 4.0 amps (this would be 3.0 ohm coil)
6cyl & 8 cyl, max amp draw 8.5 amps (this would be 1.5 ohm coil for both)

And finally I talked to them (but non-tech person)
6cyl use 3.0 ohm (no ballast) for mainly city driving
6cyl use 1.5 ohm (ballast not needed) for highway driving


So until I manage to get a real tech person from them, am I better off with
3.0ohm coil, no ballast?
1.5ohm coil, with .6 ohm ballast? (which seems ideal to me as it splits the difference between 1.5 ohm/8cyl and the 3.0ohm/4cyl)

From a longetivity standpoint, I can see the 3.0 ohm coil as less amps will go thru ignitor, but I have more potential volts/amps with the 1.5 ohm coil /.6 ohm ballast combo.......


Comments.......


thanks

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

The factory point-type ballast resistors are supposed to get hot and greatly increase their resistance at low RPM, then cool and decrease their resistance at high RPM - from about 0.5ohm to 2.5ohm.

The factory electronic ballast resistors stay 1ohm all the time.

The ads say the Pertronix II module has clever dwell circuitry inside to limit the current; the factory style electronic ignition doesn't. The point-type bulkhead is marginal even for a stock-type electronic ignition. A >1V drop is not unusual.

If you're using points or a factory style ignition module, I'd recommend either the 3ohm coil w/o ballast or (probably better) a 1.5 ohm with the factory ballast. If you're using the Pertronix II, you probably can use the 1.5ohm coil w/o ballast, but I'd check the directions for the Pertonix II 1st.

It's a pertronix I

_________________
Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

i suggest you get rid of that thing while you still can. i hooked it up on my car once (with tech guy on the phone) and had it blow on me. Then i had it hooked up by a place petronix recommened and it blew on me again.

trash it

just do the chrysler conversion

buy the harness from SummitRacing.com

go to pepboys and get a dist. from a car with elec. ignition

and buy the orange box.



just my opinion.

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70 Plymouth Valiant 4dr

I cannot answer the coil question-- but I have been using the petronix 1 for some time & I'm glad I switched -- I used the factory coil for some time
& just switched to an aftermarket new coil (summer) --during an engine swap.

The most noticable difference on my car was quicker starting & smoother idle-- all I had changed was the pertronix vs points.(do not know how old the points were-- just don't like changing them)

By the way it's a 62 valiant with a newer 65 motor.. (50k miles) 225 has much better acceleration than the 170!!! Glad I switched!!

I'm fairly certain that the Pertonix I does not have internal current limiting, so I would expect that the 1.5 ohm coil + no ballast would overload the wiring and possibly the module too.

An advantage of running the 1.5 ohm coil + ballast is that the ballast is bypassed when cranking, allowing you to temporarially run what would normally be an excessive current if used continuously through the coil. The starter relay provides the coil current while cranking so you don't overload the underdash wiring.

I did talk to one fellow who ran his point system w/o a ballast w/ a more-or-less stock coil for about 6 months before, as he put it, "the coil exploded".

Ok, here's the summation

All the solutions would work (1.5 no ballast, 1.5 ballast, 3.0 ballast) on a 6 cylinder that's for everyday driving.

With a 1.5ohm coil he did prefer the stock ballast, but without saying you'll fry things with the 1.5 coil, he felt the best solution was the 3 ohm coil with no ballast (there's plenty of spark energy, and there's less heating of the module)and is what he'd use.

There wouldn't be a starting issue with 3 ohm coil (compared to a 1.5 when ballast is bypassed), and you'd still wouldn't have a starting issue even if you fell back to points with 3 ohm coil

And don't use a ballast with 3 ohm coil!!


BTW, the 3 ohm coil doesn't have an internal resistor (i.e. it's not an 1.5 ohm coil with a 1.5 ohm resistor). The 3 ohm coil is wound internally different than a 1.5 ohm coil.

BTW2, check this out
http://www.bgsoflex.com/igncoil.html (it's based on v8 )
summit has the coil specs of various coils you can try.

A ballast resistor will drop voltage that the coil sees, so a low ohm coil with a ballast resistor can actually put out less energy than a higher ohm coil without a ballast resister

_________________
Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes