Chrome ECU and Ballast Resistor

[mojavered]

Well, I hope that it will work out.  If it is wrong, I would rather know before I hook it up.  Thanks for your help  and info so far!

[UKcuda]

I think I would be happier with something like this maybe:

http://www.summitracing.com/parts/PNX-40001/

I'm not necessarily fond of Pertronix stuff but a lot of people seem to like them and I have to admit it is not an expensive coil for what you get.  With your ballast you would have a good 9 volts across it and 2.3 ohms total in the circuit, which is a little over 5 amps stationary and about 6 amps (intermittent) running.

 I would think the ECU should be within it's comfort zone with that.

Your MSD coil is max 45Kv and this one is only max 40Kv, but if you factor in that you would only have 6 volts working on your MSD and 9 volts working on this one, then this one still comes out with a lot bigger spark on the HT side.

It is also specced with a much longer spark duration than the MSD - which some people think is an advantage, though I can't speak from experience on that.

[mojavered]

Thanks UKcuda!  Maybe some others will chime in on this?

[dodj]

One variable that is hard to determine is impedance. Resistance and impedance are related, but different animals. You won't get the impedance of a coil with a meter. You will get it's resistance. Wound coils develop CEMF (counter electro-motive force) which is sort of an electrical resistance caused by magnetics. (over simplified, but this isn't a physics class) So your overall impedance is actually the resistance you measure with your meter plus the resistive effect of the CEMF.
If MSD recommends a .8 ohm ballast, that's what I would use.

[mojavered]

Since I already have the combo, I am going to use it.  Hopefully soon I will be breaking in this bad boy and will be able to see how they work.  Thanks!

[UKcuda]

One variable that is hard to determine is impedance. Resistance and impedance are related, but different animals. You won't get the impedance of a coil with a meter. You will get it's resistance. Wound coils develop CEMF (counter electro-motive force) which is sort of an electrical resistance caused by magnetics. (over simplified, but this isn't a physics class) So your overall impedance is actually the resistance you measure with your meter plus the resistive effect of the CEMF.
If MSD recommends a .8 ohm ballast, that's what I would use.

That's a fair point.