Quote:

Quote:

Do a search. This exact subject has been seriously thrashed in the last 2 weeks.

Your next question will/should be "which ballast resistor do I need to use". You are going to get wildly conflicting answers to that one. They will come up in the above search also.

[edit] Ok it might be more like 2 months instead of 2 weeks. Sorry, the older I get the faster time flies. Do we have an old guy smiley? Maybe this one.

The MSD Blaster2 will work fine but there is widely differing opinion about the correct (if any) ballast resistor to use with it. According to MSD the Mopar boxes need a total of at least 1.5 ohms to prevent overheating the transistor. The blaster2 is a 100 turn, .7ohm coil and you should therefore use at least a .8 ohm ballast(which incidentaly is the one they sell). This is not to protect the coil, it is to protect the transistor on the box from overheating. The .25 ohm ballast that Mopar sells was intended for racing with a chrome box and a similar .7 ohm 100 turn Accel coil. "Not recommended for continued operation at speeds below 3,000 rpm for more than 30-minute periods." For street use with either a chrome or orange box and a blaster2 or equivalent use a .8 or 1.0 ohm ballast. Some people on here do not agree and have apparently used the .25 ohm or no ballast for many years without box failure. Others have not had that same experience. I would suggest that if you choose to roll the dice and run less than a .8 ohm ballast that it might be a good idea to have a spare box in the trunk.




Lets set the record straight...
Direct quote from the Mopar Performance catalog, page 119..

" With the Blaster Coils and Mopar ignition kits P3690426, P3690427 and P3690428, use the 1/4 Ohm ballast resistor (P2444641)"...

Note that many installs may mix/match various ignition components, but IMHO what the factory says to use is a good starting point...

Just my $0.02...



I can quote also. "Ballast Resistor, for Mechanical Advance Distributor, Using P3690560 and P4876832/33 Coils. 1/4 OHM, Race Only "

The reason it says RACE ONLY is because this is actually a mismatch of parts. For best all out performance these coils want 12 volts but the ecu's are not designed to switch that and should have a .8 ohm resistor for street use with this coil. The .8 ohm ballast WILL reduce the coil output(certainly not optimal but usable) but keep the ecu happy. For RACE USE you can get away with the .25 ohm resistor. Here is another quote for you.
"Not recommended for continued operation at speeds below 3,000 rpm for more than 30-minute periods."

For this reason I don't use a Blaster coil on a street car. It is a good race coil with 1/4 ohm or no Ballast but there are better choices for use on the street with a Mopar ecu.

Last edited by GomangoCuda; 08/23/11 12:09 AM.
In theory, there is no difference between theory and practice. In practice, there is.