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Attention Chrome Ignition Box users

prostockstan

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After finishing my friends 512ci cross-ram engine We decided to replace the Orange Box with a chrome box ignition. Installed new box and new Year One wiring harness. The car ran pretty well after tuning the carbs for a few hours. When we were convinced the tune up was sufficient we parked the car. The next week we went to start the car and it would start and immediately die after letting off the key from start mode to run mode. The coil voltage was 3-5 volts. When we disconnected the Neg. trigger wire from the coil the voltage went right up to 12.6V So we thought the new chrome box was causing the problem. It acted like the built in rev limiter was stuck on. We put the old Orange box on and the problem went away. Remember the car started every time but when you let off the key it would immediately die. Many posts said this condition was the ballast resistor or the start switch. We tested and or replaced all these items and it still never would stay running. From this situation we learned that a Bad Chrome box will cause the same problems. It was like an internal short within the box.. Anyone with the same issue in the past please chime in and let me know your experiences.

Thank You: Stan
 
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never had an issue with the chrome box. the chrome box doesn't have a rev limiter, or at least the ones i have don't. i do add a ground wire to all my boxes.
 
I was told they are good for about 8000 RPM. wasn't sure if it had a built in limiter or not. I was told they pull out timing later in RPM. It's a shame the new chrome box only lasted one day. Maybe it was just a fluke. We might just try another new one and see.
 
i know the ones i have have a very stable dwell so i'm not sure about them puling timing. there are people who claim they pull timing but have never given any exact proof. i think the lesser boxes like the orange may pull timing due to dwell changes. i want to try the new FBO box with the rev limiter.
 
The last Mopar chrome box I ran was accompanied but a big yellow Accel coil, a Torker 440 intake and I was lookin real good. That was a LONG time ago! I'd probably upgrade to a capacitive discharge ignition like you are planning. The rev limiter will help with all of the tire spin!
 
Sounds like a bad Chrome box. I had the same issue with an Orange box once. It was the only time I had trouble. I use the Chrome box as a back up to the ever popular failing aftermarket box. The MSD has been my biggest offender for failing.
 
I have read that the majority of failures occur with the orange boxes, not the chrome or gold ones.
 
i got away from the msd/jacobs gadget boxes years ago. i think they have a place but not on my cars. when i did a track test and dyno test back to back and seen no difference for the money and wiring hassle i went back to the factory inductive systems.
 
Don't know if this helps or may be a possible cause to the OP's box failure.
Per MP application chart, the chrome P4120534 box is mated to P3690560 coil and P2444641 ballast. Also has a side "note not for prolonged use under 2000 rpm".
 
1) I ran a chrome box on my daily driver Valiant for a few years without trouble. -30, 105 degree F, sitting in traffic, whatever it didn't have a problem.

2) If you have a cam with 70+ degrees of overlap the capacitive discharge should help clean up the idle.

3) If you like walking home run an Orange box and if I see you I'll pick you up on the highway lol.
 
This is how things get funny. I bought this orange ECU Mopar box in 1999 you see here on my car and we have been using it since then with never a failure or any problem. It does not pull timing as I checked it and when we took it of my boys Dart in 2006 so I could use it on my 63 we put MSD on his Dart. The MSD works good but the car is no faster and runs and starts the same as before which was fine. I can tell you it never miss's a beat on my car and it has run 10.70's using it. It is also very consisdent using the orange box. I have had a bad ECU do what your car is doing before. It sounds like an internal problem in the 12 volt run circuit in the box as it functions when the key is in the run posistion and may have an internal problem. Ron

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I have very old Orange boxes that won't die. The problems seem to be with the new boxes. Out of curiosity Ron what cam is in that engine?
 
i've been playing with mopar's ecu's since 1973. i've only lost one out of many; a newer orange box. i just ordered the FBO kit; box, coil, ballast eliminator.
 
I have very old Orange boxes that won't die. The problems seem to be with the new boxes. Out of curiosity Ron what cam is in that engine?


Its from Dwayne Porter as its a custom grind he speced for me. Its a solid flat tappet thats 264 & 270 @ .050 with .585 and .592 lift and a 110 LSA. I have it in the eng on a 106 ICL. It works great for me as I have no problems running on 92 pump.

I agree as my two orange ECU were bought in the 90's and both are still going strong. Ron
 
Doing a little quick math I'd guess that the overlap on that cam is less than 70 degrees. Do you have any numbers for when the intake closes and exhaust opens by chance? It sure runs good!
 
I have a orangeb box that's older then dirt hanging around for just in case the chrome box fails. Its sad when you carry extra parts in the car because you know there all junk and don't last I went threw 4 voltage regulators before I got a good one that worked . Made in Mexico or China oh well
 
i've been playing with mopar's ecu's since 1973. i've only lost one out of many; a newer orange box. i just ordered the FBO kit; box, coil, ballast eliminator.

Let us know what you think of them. I just bought the same set up for both my cars, but won't be able to test them until spring.
 
Never had a problem with orange boxes on a few cars, I switched to the FBO setup two years ago on the GTX and it runs great especially at higher rpms, main reason I switched is for the rev limiter.
 
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