1974 Brain Box saves the day.

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George Jets

George Jets

1967 Dart 2 Door
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Was heading out to a local car gathering a couple weeks ago, and a no start on my '76 Truck.

Turns out the 1 year old replacement brain box failed.

I had a well used 1974 5 pin brain box from my '74 Dart that I had replaced because all the goo on the back had melted out from the hot sun in Florida.

Swapped in the 46 year old rough looking brain box and I was good to go. Made it to the gathering right on time. Worked no problem.

Used parts are proven parts, thanks
Ma Mopar !

Got another new one in now, will see how long that one lasts.

'74 Brain Box on Right:

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Take the old one apart and find that the large T03 transistor is fake, and they use a cheap 5 cent T093 on the actual board. Remember the OEM parts were designed for 5yr/50000 miles. or in your case 45yr/50000 miles....
 
pishta said:
Take the old one apart and find that the large T03 transistor is fake, and they use a cheap 5 cent T093 on the actual board. Remember the OEM parts were designed for 5yr/50000 miles. or in your case 45yr/50000 miles....
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That is really sad. Those are simple ignitions. There is no excuse why someone cannot manufacture a reliable replacement for them. I just wish (now) that I'd stole more of them back when we had junkyards LOLOL
 
@halifaxhops usually has some good old stock aftermarket ready to go. The new stuff is trash. Points ignition parts are junk nowdays and if you have a working condenser, leave it in until it fails or replace it with old aftermarket from 50 years ago.

points4.pnga.png
 
Ha, another sucker! ProComps MSD look alike is full of...HEI boards!
fakeMSD.jpg



As Biden would say....
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Makes me want to cut open my MSD 6al..... nah! Afraid to let all the pre packaged smoke out.
 
Pishta, that is very pathetic.
Im curious of what is inside the digital 6AL. Its about 1/4 of the weight of the old 6AL's.
 
pishta said:
View attachment 1715591581
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OK @pishta, school me here.

I just cut open this failed aftermarket black 5 pin brain box.

To start off it was full of sand ????

Opened it up and that silver transistor on the external heat sink was not wired to anything, it was empty.

Looks like there were some cooling conductors from the main board chip to the heat sink on the inside, but no wiring there.

Imagine there is a small mother board with a computer chip in there like on a computer wired to the 5 pin plug.

What do you think ???

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China junk, end of story. As I said, clean it out, stick a GM HEI 4 pin in there. The sand is deteriorated potting material.
 
I cannot believe somebody doesn't produce a quality piece.. Sad.
 
318willrun said:
I cannot believe somebody doesn't produce a quality piece.. Sad.
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We should not be surprised. There does not seem to be ANY aftermarket replacement auto parts anymore, in current stock, that is "quality." It is all China ****.
 
67Dart273 said:
We should not be surprised. There does not seem to be ANY aftermarket replacement auto parts anymore, in current stock, that is "quality." It is all China
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I bought three things: A alternator, water pump and fuel pump. They were for "peace of mind". I only used the water pump. The fuel pump was obviously lighter than the fuel pump i removed, and the arm wasn't curved on the new one. I felt better re-using the old one. I tried to install the remanufactured alternator and found the adjusting bolt hole threads were striped - mostly missing. I re-used my old alternator. Just a shame in my opinion. Where is the PRIDE in the Product you manufacture?? is my question to these companies. Is the "dime" the only bottom line? How about 7 pennies and give us quality...
 
Got to gear up and make things in USA again. Quality Control with the company's name on the products, proudly displaying Made in the USA.
 
toolmanmike said:
@halifaxhops usually has some good old stock aftermarket ready to go. The new stuff is trash. Points ignition parts are junk nowdays and if you have a working condenser, leave it in until it fails or replace it with old aftermarket from 50 years ago.
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LOL so typical of the "new" stuff today. Found out about them a few years ago when I got my ecu tester. Try to stay with the older 80's and back, A quick clue if it is REAL or decent is what is printed on the transistor. You want Texas Instruments logo or I believe GE. Also with a label "replaces XXXXXXX" is another clue. And yes I have good old stock ones. Hope it helps.
 
halifaxhops said:
LOL so typical of the "new" stuff today. Found out about them a few years ago when I got my ecu tester. Try to stay with the older 80's and back, A quick clue if it is REAL or decent is what is printed on the transistor. You want Texas Instruments logo or I believe GE. Also with a label "replaces XXXXXXX" is another clue. And yes I have good old stock ones. Hope it helps.
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Did they use Motorola as well?
 
Cut open another Mopar Brain Box

This one appears to be the "Chrome Box"
5 pin

Looks like this one was built correctly with the correct working transistor that fastens to the heat sink.

Also there was no filler fine sand in this one, just the gel sealing compound like is supposed to be in there.

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Proper Transistor 034
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Fake chinese transistor on top (empty)
Correct 034 transistor on the bottom

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67Dart273 said:
China junk, end of story. As I said, clean it out, stick a GM HEI 4 pin in there. The sand is deteriorated potting material.
Click to expand...

The fine sand inside was sand, not potting material, this was brand new a year ago. The good mopar brain boxes do not have sand filler layer in them, just the sealing gel.

Thanks
 
George Jets said:
Got to gear up and make things in USA again. Quality Control with the company's name on the products, proudly displaying Made in the USA.
Click to expand...

Anybody here on FABO have the wherewithal to help identify these original mopar brain box motherboards, processing chips, transistors, and diodes.

Also help to identify some of the original manufactures of these electrical computers.

Schematics, drawings and wiring of these brain boxes.

Can reverse engineer or clean slate makeup up the new motherboards.

Want to start getting these new high quality brain boxes manufactured here in the USA.

Any ideas guys ??
I have a brother that is an electrical engineer that designs computer chips for a living and they have the manufacturing leg of the business that builds the components after they are designed..

No chinese for the mopars . . .

Mopar components pictured below:
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If you can get one apart and clean, it should be easy to duplicate the circuit, but getting original value components might be tough, as the transistors and such may be (sometimes purposely) unmarked.

The real "gotcha" on more modern electronics is multi-layer PC boards which can be a ***** to trace. I am not good at reverse engineering. Frankly it's not worth my trouble. I'm happy to use GM HEI modules--so long as decent replacement ones are still available

The other little advantage to a GM unit is that with the key in "run" and engine stopped, a proper GM module will not draw coil current
 
George Jets said:
Anybody here on FABO have the wherewithal to help identify these original mopar brain box motherboards, processing chips, transistors, and diodes.

Also help to identify some of the original manufactures of these electrical computers.

Schematics, drawings and wiring of these brain boxes.

Can reverse engineer or clean slate makeup up the new motherboards.

Want to start getting these new high quality brain boxes manufactured here in the USA.

Any ideas guys ??
I have a brother that is an electrical engineer that designs computer chips for a living and they have the manufacturing leg of the business that builds the components after they are designed..

No chinese for the mopars . . .

Mopar components pictured below:View attachment 1715592172

View attachment 1715592169

View attachment 1715592170 View attachment 1715592171
Click to expand...

It would be a fun project to reverse engineer.
Values for the resistors and caps should be pretty straightforward. It's the specs for the transistors that might be more difficult.
Go for it and see what happens. If you post as you go, people can colloborate with whatever they can contribute.

As far as producing, also think about repairing. If you can take them apart that neatly, if the parts can be sourced, just replace what's needed. Nacho was hamstrung in part because of his location made it that much more difficult to find the switching transistor.

There's a cutaway photo here but its black and white. Not really good enough to use for identifying each component.
1972 Imperial & Chrysler Ignition System Service Book (Session 292)

ps It's possible the Hi-Rev 7500 version has assembled in US. I cant recall if anyone has cut one of those open.
 
Mattax said:
It would be a fun project to reverse engineer.
Values for the resistors and caps should be pretty straightforward. It's the specs for the transistors that might be more difficult.
Go for it and see what happens. If you post as you go, people can colloborate with whatever they can contribute.

As far as producing, also think about repairing. If you can take them apart that neatly, if the parts can be sourced, just replace what's needed. Nacho was hamstrung in part because of his location made it that much more difficult to find the switching transistor.

There's a cutaway photo here but its black and white. Not really good enough to use for identifying each component.
1972 Imperial & Chrysler Ignition System Service Book (Session 292)

ps It's possible the Hi-Rev 7500 version has assembled in US. I cant recall if anyone has cut one of those open.
Click to expand...

Thanks
That is a nice picture to see what is going on, on one side of the board before the epoxy goes in.

Screenshot_20200908-182158_Gallery.jpg
 
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