Mopar chrome box resister required?
- Thread starter Mike 340
- Start date
-
The pictures of the orange box and resister are from my MP performance distributor kit. I know the box works as I have tried it and my engine runs. Didn't run it long as I didn't want to cause it any problems.
Ask @halifaxhops.
None of the MP recommendations are high enough for my liking. I don't think any of them are over 1 ohm. When the resistors get hot, that resistance drops. I prefer to run a 1.5 or 1.7 because I've had trouble burning up boxes at the recommended .5. And yes, the Chrome Box needs a resistor. In fact, even my Hi Rev 7500 got hot and cut off when I had a .5 resistor on it. I put a 1.7 on it and it's done fine.
Professor Fate
Push the button, Max...
Yeah that^^^^^. None of those are high enough, IMO. But use what you like.
Professor Fate
Push the button, Max...
Agree- but my main reason to post that was to confirm that yes, the Chrome boxes do require a ballast resistor. The value of which ("valve" -sic- in the chart) seems to vary quite a bit even for the same RPM usage. The "preferred" (*) value is also the highest- the .80 ohms built into the Accel 150001 coil. Makes me think you're right that a higher rated resistor would be better, esp. on the street- since initially Mopar didn't even recommend using the Chrome box on a street engine. Popular theory at the time was that they burned up at lower RPM usage, so the higher ohm rating should help them survive.
But who decides "require"? Mopar Performance? What I mean is, "I" will always run one with a Mopar style ECU......but I've seen a lot of guys just leave um out. For years. And not one failure. Then I've run the .5 and burned a few boxes up years ago and made a Hi Rev 7500 box stop firing until it cooled back off. So what the heck? LOL That's why I err on the side of caution and use a higher resistance rating.
There are 2 pin and 4 pin ballast Resister.
The 2 pin is typically for points or 4 pin ECUs
The 4 pin is needed for real 5 pin ECUs
THAT SAID...
You have a 4 pin ECU so you need a 2 pin ballast that your coil manufacturer recommends. The ballast is only to protect the coil in your setup. Does not have any effect on your ECU.
your coil's amperage draw can have an effect on your ECU. If it's a stock coil, no concern, if it's a high output it MIGHT.
The 2 pin is typically for points or 4 pin ECUs
The 4 pin is needed for real 5 pin ECUs
THAT SAID...
You have a 4 pin ECU so you need a 2 pin ballast that your coil manufacturer recommends. The ballast is only to protect the coil in your setup. Does not have any effect on your ECU.
your coil's amperage draw can have an effect on your ECU. If it's a stock coil, no concern, if it's a high output it MIGHT.
OR run an ignition that doesn't require a resistor.
I was thinking about that not long ago when I was trying to get my 64 Poly to start with a key. The PO had converted it to Mopar Electronic and aparently had troubles. The only you could get it lit was to jump the coil off the battery.
I got ahold of Hoppy and got the right parts.
hoppy's a good dude. I don't care what they say about him. LOLI was thinking about that not long ago when I was trying to get my 64 Poly to start with a key. The PO had converted it to Mopar Electronic and aparently had troubles. The only you could get it lit was to jump the coil off the battery.
Boy there have been a lot of ignition related issues around here lately.
Because there are some really CRAPPY parts being sold. I HOPE this new Blueprint slant 6 ignition is going to be as good as I think it is. I'll find out hopefully this week how it runs, at least.
Please do not run a .25 ohm resistor for the chrome or gold box on the street. Drag only to get the most RP; s out of the box and it COOLS down between runs. Run around a 1 and you will get 7K RPM out of it and it will be fine. General rule lower resistor more heat higher RPMS in a nutshell. Also there is more than one chrome box Mopar made and the aftermarket ones are just run of the mill stock boxes.
Last edited by a moderator:
All charts from older MP Catalogues.
If it's a 4 wire 2 pin is fine as long as it's the correct ohms
The more I look at the information provided here that this is not a street application item and I should stick with my orange box which works fine.
Thank all of you for your replies, I am just trying to learn if what I have can be used for a street application.
Thank all of you for your replies, I am just trying to learn if what I have can be used for a street application.
QuickDart360
Well-Known Member
So the 4 prong/pin stock ballast is rated to how many ohms? I run the stock 4 pin/prong with the chrome mopar performance box! Is this ok? I've had it this way a while not sure how long but has run fine this way. Also using an MSD blaster 2 coil.
starts on .5 and runs on 5 ohms. 5 pin ecu Never got the 5 ohm side?
Last edited:
Sure it can a bit overkill but do not use a 1/4 ohm resistor. I know of chrome boxes running for years on the street with a higher ballast resistor. Todays new boxes suck so use a older one of you can.
-
