Hi All,
I'm pretty new to mopars, but have a recently purchased '70 Challenger that was modifed many times by previous owners. The real problem is I'm not sure of what I'm starting with, since nothing seems to be stock and I have little info from the previous owner.
This weekend I installed some TTI headers and thought it would be a good time to change the plugs, cap & rotor. While I was at it I purchased a MSD Blaster 2 coil, thinking it would be a good upgrade to my ignition system. Reading the specs, I found you need a 0.8 ohm ballast resistor if running points, and I think for a stock electronic upgraded system too.
This is where I'm confused. I found that I have a mopar orange ECU (P4120505) and what appears to be a non-stock ballast resistor already in the car. I checked the resistance and measured 0.7-0.8 ohms. The only number I see on it is US Pat. 254186, which appears to be non-mopar from what I can find on-line. Is this resistor the one supplied with an orange box upgrade? And since this is so close to the MSD 0.8 resistor spec, do I need to buy a new one? Seems like I should be able to replace the coil with no other changes.
BTW, I also have a '68 charger off the road that has a mopar chrome ECU (P4120534) in it, and I also found the same ballast resistor installed. Again, I have no history on that car. But I was wondering if I should use the chrome box on the Challenger as an additional upgrade. Any disadvantages to using it? (The Chally has a 383)
Thanks for any help!
Pete
