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79Vantucky

78/79 ignition compatibility?

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Hi all, just bought a ‘79 Brat GL that came with a ‘78 Wagon motor. After dropping it in and trying to get it running, I suspect the ignition equipment in the Brat (coil with Hitachi transistor box) and the disty in the ‘78 motor (older points style, I think Hitachi from what I’ve read) aren’t compatible.

I found a harnes with blue and red coming from the transistor box next to coil- does this plug into a newer electronic disty?

Would the ‘79 have come with electronic ign from the factory?

I’m just trying to get it running for now, so not looking to swap to electronic just yet if I can help it- if the car is set up for electronic, is there anything I can bypass/rewire  for now to get it to work with the points?

Sorry if this has been beaten to death, i’ve been scouring and haven’t found answers quite yet...us young guys have been spoiled by coil on plug...:blink:

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Yes , the 79 is the year the line went electronic ignition. 

I’ll get back with more info soon. Can you add more details about what happens when you go to start it ? 

Good alternator , voltage regulator , and fuel level thru the sight port in the float bowl chamber ?? Just hitting some basics to get you rolling.

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that points distributor can't be modified to work, the 4 pointed diamond on the shaft is different, i already went down this road a year ago, and again 3 years ago.

my 79 wagon's ignition control module went out, so since i couldn't find a replacement since it's a 1 year oddball, i just went to Autozone and special ordered a 1975 Subaru GL distributor (you'll have to know people in the back since only commercial accounts can order this in store, im sure there's some online) and converted the wagon to points, the shaft that goes in the block is like a hair too wide, so it will need to be sanded down just by hand for about 2 minutes, it's barely any, and then modify the plate to bolt and hold the distributor in place since the screw on the point's type comes from underneath, unless you have that plate already from factory, 8 degrees BTDC is where mine is at, good power, and it doesn't pick up too much temperature yet. the dwell for the points gap i think if i remember correctly is .028in, would have to look at my book. also the spade terminal poking out of the distributor goes to the negative on the coil, that's your signal wire. just keep in mind, that vacuum advancer on the points type distributors is really rare, suck on it and see if the internals move, that's how one would test it, if it doesn't work, the car will only have about 1/10th of the power, and back fire like crazy, but it'll idle just fine.

for electronic magnetic pick up distributor type, you'll need a different style shaft on the distributor, different plate for the things to sit on, and that half circle that's a weak magnet that picks upsignals from the shaft. theres a blue and red wire that plugs in to the half circle moon looking thing in the electronic distributor.

Edited by Subasaurus

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Distributor is mounted in the motor and the points break as they should-  is there no way I can bypass the transistor ignition box? Seems like you could jump the distributor signal wire straight to coil (-), but I could be mistaken.

Moosens, haven’t gotten as far as testing everything just yet- car (truck?) has been sitting for about 15 years. Power is getting to the coil from ign switch, but cranking yields no spark. We’ve cleaned up the contacts on cap/rotor/points for now but figuring something isn’t hooked up right.

Thankfully we have spare charging system parts, so we’ll test those when we can get it to fire up. Went through the carb and it appears to be working correctly, but still need to test fuel pump.

Thanks. -CK

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Sorry to smear a sale over this but I’ve got some factory service manuals with the wiring diagrams and everything.

Might be able to get the same info online. These younger folks know better than me where that stuff is available. 

I always thought the 79+ etron disty drops right in. Did I miss something or do you still have the 79 engine and disty ? 

 

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On 11/20/2018 at 5:22 PM, 79Vantucky said:

I’m just trying to get it running for now, so not looking to swap to electronic just yet if I can help it- if the car is set up for electronic, is there anything I can bypass/rewire  for now to get it to work with the points?

Sorry if this has been beaten to death, i’ve been scouring and haven’t found answers quite yet...us young guys have been spoiled by coil on plug...:blink:

Sure,Remove the connections to the transistor box and run a wire from the ungrounded  side of the points to coil negative

Bobs your uncle.

Point style coils normally have a little higher resistance,but,you should be OK.

Edited by naru2
coil negative not positive-DUH!

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once you get that vehicle running, few things to note, if the vehicle backfires after turning the vehicle off, either you need to add a capacitor to the distributor, replace the capacitor if it already has one, your timing is too advanced, or your fuel jets are too big and either need to decrease on them or replace the jets from wear and tear.

dieseling? try hooking up a vacuum gauge, calibrate your air to fuel mixture until you reach around 18 inches of mercury (or more if the vacuum lines and piston rings are of that great of shape), keep going until that vacuum needle begins to dance around (becoming unstable and starts decreasing), then go back half a turn, that should do it.

Edited by Subasaurus
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Thanks for the help all, turns out everything was hooked up correctly (we took off all the transistor connections per naru2’s response) but there was a wiring issue in the harness. We jumped a wire from disty to coil and had immediate spark. Much work left to do, but she runs, charges, builds oil pressure and idles like a champ. Next task, find jump seats...

Edited by 79Vantucky

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make sure the fans kick on before overheating occurs, the temperature switch located on the ratiator go out all the time, i just have mine always woking with ignition key on, with an override switch between the seats for really cold days, or long highway driving, just have one that lights up red so that you don't forget it's off.

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