Correct ballast resistor for standard to electronic conversion

[RJRENTON]

Problem is , none of these Mopar ECUs are made anymore , and even the ones that where made the last ten/fifteen years where at best poor quality

Part I struggle with , is trying to match up all this Chinese junk today , mostly Coils/ECUs and put a decent system together with mismatched components that actually performs


Totally agree all the newer stuff sucks for sure. I try to keep the older nos/nors parts down to a decent price when I find it but it is getting really rare and the new stuff absolutely sucks.

A curiosity question....
Is the lack of a reliable, reasonably priced, available, perhaps with adjustable RPM's limited, a "universal" ECU as an opportunity to design and manufacturer what is needed? Rather than the units presently produced with the highest profit margin and lowest quality components.
I'm presently trying disassemble a failed Mopar orange box ECU, to determine which internal component failed and the reason for the failure. And possibly improving the design to eliminate the sensitivity to coil requirments and the associated switching transients and to POSSIBILITY of eliminating the need to use a ballast resistor, finally ending the ongoing controversy of the need and value of said resistor.
This effort will take some time.
Bear in mind that the coil produces the high secondary voltage when the ECU (and associated internal components) turns OFF the coil's primary voltage (and current) and therefore must absorb these induced voltage transients repeatedly, and as the RPMs increase, the peak transient voltage also increases. The coil's inductive reactance also affects the charge and discharge time as well as the associated inrush current, which requires the ECU to absorb these additional parameters continually.
BOB RENTON

 

[Daves69]

I'm curious if someone knows they (or someone they know) actually hurt their MOPAR ECU due to the highlighted.......

 

[HALIFAXHOPS]

A curiosity question....
Is the lack of a reliable, reasonably priced, available, perhaps with adjustable RPM's limited, a "universal" ECU as an opportunity to design and manufacturer what is needed? Rather than the units presently produced with the highest profit margin and lowest quality components.
I'm presently trying disassemble a failed Mopar orange box ECU, to determine which internal component failed and the reason for the failure. And possibly improving the design to eliminate the sensitivity to coil requirments and the associated switching transients and to POSSIBILITY of eliminating the need to use a ballast resistor, finally ending the ongoing controversy of the need and value of said resistor.
This effort will take some time.
Bear in mind that the coil produces the high secondary voltage when the ECU (and associated internal components) turns OFF the coil's primary voltage (and current) and therefore must absorb these induced voltage transients repeatedly, and as the RPMs increase, the peak transient voltage also increases. The coil's inductive reactance also affects the charge and discharge time as well as the associated inrush current, which requires the ECU to absorb these additional parameters continually.
BOB RENTON

@stephan holts has that down, depend what ecu there are dozens out there.

 

[HALIFAXHOPS]

I'm curious if someone knows they (or someone they know) actually hurt their MOPAR ECU due to the highlighted.......
View attachment 994970

Some of the "new ones" have dummy transistor's. Buyer be ware.

 

[RJRENTON]

I'm curious if someone knows they (or someone they know) actually hurt their MOPAR ECU due to the highlighted.......
View attachment 994970

FYI....The power transistor's case is the collector junction, whose potential voltage is at 12 volts DC when the power is on and engine NOT running. Its when the engine is running, the coil's collapsing primary winding current at each spark occurrence, generates an approximately 200+ volts, which is impressed on the transistor's case across the emitter-collector junction and dissipated thru an internal dV/dT snubber circuit. This dV/dT circuit is usually a low ohmic value resistor (33 ohms or so) in series with a capacitor (typically .22mfd or so) to limit the INSTANTANEOUS impressed voltage spike, by absorbing it, to below the junction threshold's breakover value.
BOB RENTON

 

[RJRENTON]

@stephan holts has that down, depend what ecu there are dozens out there.

@stephan holts has that down, depend what ecu there are dozens out there.

Please supply his contact info to my PM box so I can communicate our findings. I cannot believe there dozens of fifferent ECU's but minor variations of the basic elements and principles. My intent is not to duplicate his effort or findings but to perhaps augment them and ultimately produce a universal ECU that works with all available coils, especially those that seek the "best" ignigion device. Thanks in advance for your help.
BOB RENTON

 

[HALIFAXHOPS]

Bob he hangs out on FABO a lot but is a member here. He sells the good coffee. Contact him a good guy. I was going to do exactly that but just one of me so I have to pick my battles.

Hey @Stephen Hotz

 

[RJRENTON]

Bob he hangs out on FABO a lot but is a member here. He sells the good coffee. Contact him a good guy. I was going to do exactly that but just one of me so I have to pick my battles.

Hey @Stephen Hotz

THANK YOU FOR THE INFORMATION .... I'll correspond directly.....perhaps we can help each other...
BOB RENTON

 

[Bee1971]

Anyone watch - Throwing Sparks

https://www.motortrendondemand.com/show/engine-masters/645/

 

[383man]

And as a side bar to my #49 above, the ignigion coil is really an auto transformer, where the end of the primary winding and secondary winding are physically connected at a common point. A typically ignition coil, has three (3) connections. A positive (+) connection, a negative connection (-), which is the common connection point for the windings, and the high voltage connection. A "true" transformer has isolated primary and secondary windings, connected solely by the magnetic field and the silicon steel core laminations, which allows the magnetic lines of force to pass thru both sets of windings. Energy losses can be summerized by: core losses (the magnetic energy) AND copper losses (losses due to the resistance of the windings). These losses cause internal heat build up, sometimes to the point of insulation failure.
BOB RENTON

And as a side bar to my #49 above, the ignigion coil is really an auto transformer, where the end of the primary winding and secondary winding are physically connected at a common point. A typically ignition coil, has three (3) connections. A positive (+) connection, a negative connection (-), which is the common connection point for the windings, and the high voltage connection. A "true" transformer has isolated primary and secondary windings, connected solely by the magnetic field and the silicon steel core laminations, which allows the magnetic lines of force to pass thru both sets of windings. Energy losses can be summerized by: core losses (the magnetic energy) AND copper losses (losses due to the resistance of the windings). These losses cause internal heat build up, sometimes to the point of insulation failure.
BOB RENTON

I have seen coils where the primary and secondary windings actually connect at the coil + post which was how most coils for points were that I saw and some where they connect at the - post also as you stated. And some coils dont connect the primary and secondary windings at all as some coils just ground the secondary winding and the other end of course goes to the dist cap. Course coil pack coils have both ends of the secondary windings going to and firing a plug since they fire two plugs at the same time and their secondary windings do not connect to the primary windings. Ron