1974 Brain Box saves the day.

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Here is s brain box on Ebay that is supposed to be made in USA

Looks like there could be a working Motorola Resistor on this one.

Would like to cut it open and see if that resistor is a real working one or fake like the chinese version.
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Transistor you mean. How about a real link instead of whatever screenshot that is?
 
Transistor you mean. How about a real link instead of whatever screenshot that is?

Yes Transistor

These look like the good USA versions with the proper working external transistor.

Ordered in the pair as these were the last 2 USA New Old Stock they had on hand. Want the good USA stuff when a person can find it.

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Here is a way for people to start identifying the chinese fake transistor brain boxes.

The chinese shinny fake transistors stand taller like a Top Hat, are narrower than the OEM, have no writing or branding on them, and they use the Fine Threaded Screws to mount them. OEM mopar transistors use course threaded screws to mount them.

The thing is the OEM transistors act as a switching devise and create heat, so the aluminum / cooper heat sinks they attach to pulls the heat out of them.

The fake chinese transistors are empty and don't attach to anything, so the heat that builds up on their internal board has no way to get out, especially being encased in their fine sand that holds the heat in too. So they overheat and fail internally. Short lifespan parts, not if it will fail . . but when.

Fake chinese transistor on the top, OEM style on the bottom:
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chinese cheeper internal board, encased in sand.
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Fake:
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OEM style good quality board encased in the proper epoxy.
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OEM style for me . . .
 
Also LOL the case of the real one will shock the livin' $heet outta ya!!! (It is the coil neg terminal)
 
the small transistor they use today T0-220 is rated at 150W, the TO-3 is rated at 300W and the case is the collector on the TO-3. The 220 has a center pin as Collector or may have only 2 pins and uses the heat sink as the collector, ala TO-3. Either way the TO-220 is just a smaller cheaper version of the TO-3 with less power handling. the TO-3 is not made for pennies anymore and the supporting electronics of the newer boards probably does not spec that high of a power handling capacity. @George Jets your small transistor heat sink should contact the metal of the cover securely to dissipate heat only, probably insulated, not used as the collector circuit anymore for safety reasons (ie. 400V potential at the case of the old ones) you can thread a hole in that heat sink, put some thermal compound on it and screw it down to the real heat sink for added thermal conductivity if your so inclined. Making a new board with that schematic will get you an old style circuit but the switching transistor must be spec'd at the old values to get a 'better' board. Today, a chip can do what 50% of the passives on that circuit can do at about .30 cents.
 
Just curious, does anyone had a cut opened Rev-A-Nator? Curious as to what the insides of 1 look like.
Thinking of buying one, just for the adjustable rev limiter. Still looking...
 
This is a very interesting read but man I have no freaking clue what yall are talking about!!! So the round metal part in the center (transistor?) Is fake in the new ones? Or the old ones? What does that supposed to do?
 
Pretty cool if you can make USA made units again.

im thinking of going with the whole FBO ignition and using his distributor.
I don’t know yet.
 
The TO-220 transistor would likely work if they properly heat-sinked it. That is what the big screw-hole is for, and you see them bolted to a thick heat-sink in every commercial product. As 67Dart273 suggests, for a factory look, gut the box and hide a GM 4-pin HEI inside (search posts). It needs heat-sinking too and a ground connection thru its case. For best look, gut an OE ECU. If you don't care about factory look, use a GM 8-pin module and coil. A factory GM cable connects the two. Easy pick from a 1985-95 GM V-8 truck, and many posts here. You can then toss your ballast resistor. Your Mopar e-distributor can trigger it. Stronger spark, so might need 8 mm plug wires. You can grab good silicone plug wires from a Mopar Magnum V-8 to fit a small-block. They are nicely labelled by cylinder.
 
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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Older is better....

My son had issues withb his '28 Model A.... Installed new Chicom ignition parts and it ran worse.

I called my 90 year old buddy Marley who knows T and A' s inside out. He brought over some 50 year old ignition parts and the truck ran flawlessly....lesson learned.
 
From what I can tell if the transistor is marked Motorola, RCA, or Texas instruments it functions. I have a tester for them and most of the "new" ones fail at high rpm also. I only deal with pre 80 stuff. @Stephen Hotz is working on a fix for these that should not fail at all. He is taking old cases also if you want them to go to a good cause.
 
...The TO-220 transistor would likely work if they properly heat-sinked it. That is what the big screw-hole is for, and you see them bolted to a thick heat-sink in every commercial product. ...
Proper heat sink on a TO-220 board (Rev-n-Nator). you could mod the Chicom stuff if you wanted to get the TO-220 a place to send its heat.
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I think the sand in them is kind of acting like a desiccant. Way cheaper than potting. I run from them.
 
It is amazing how many different ones are around, all different. At least with oem Mopar you can tell what they are supposed to do by the color combinations. Aftermarket no way. Just junk in a chrome box usually. Kind of learned a lot of this over the years. One of the biggest hold backs is having the proper ballast matched to the box. That's a whole can of worms there also.
 
From what I can tell if the transistor is marked Motorola, RCA, or Texas instruments it functions. I have a tester for them and most of the "new" ones fail at high rpm also. I only deal with pre 80 stuff. @Stephen Hotz is working on a fix for these that should not fail at all. He is taking old cases also if you want them to go to a good cause.
Good news # makes sense recycle and re-use with improved product !
Keep group posted if this individual has a useful product some folks to like the Chrysler system.
It is amazing how many different ones are around, all different. At least with oem Mopar you can tell what they are supposed to do by the color combinations. Aftermarket no way. Just junk in a chrome box usually. Kind of learned a lot of this over the years. One of the biggest hold backs is having the proper ballast matched to the box. That's a whole can of worms there also.
Yes sir - I started horting up the 1/4 ohm Chrysler resistors a few years ago . * I wonder if the gold Box Mancini sales is quality ?
 
Those 1/4 ohm are gold now usually around $50 if you can find them. I have seen them get into bidding wars also. No idea on their box but they usually have great products along with Erhnberb? Might have spelt it wrong.
 
I come across them on occasion. I just never know what I am getting in large lots of ignition parts I have some gems for sure.
 
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