Electronic Ignition upgrade for your 320
- wayno
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Electronic Ignition upgrade for your 320
I have done a lot of upgrades over the years, but I have to say right now this is hands down the best upgrade I have ever made to a 320, my 1963 Datsun L320 has been a bitch to start for years, everything had to be perfect for it to start and I still had to turn it over quite a while before it would even try to hit/start, well yesterday and this morning I modified a matchbox distributor, put it in the truck, wired it and I removed everything(wires) that would smoke my harness/generator as it is still positive ground, wired the EI distributor to the EI coil(neg ground), made it so the starter would work, pulled the choke on, pumped the pedal 2 or 3 times, I left the key in the off position and made sure it was in neutral as I am doing all this from the engine compartment, gave the coil power, hit the starter trigger and that thing started in less than a second stone cold, never in the entire time I have owned it has it started like that even after it was warmed up, shut off, and started again.
OK, this is how I did it, first you need a matchbox distributor from an L block(Hitachi D4K) from a 1979 Datsun 620 or a 1980 Datsun 720, and you need your E1 or J13 series distributor, there are likely other L block cars that had the matchbox also.
The Matchbox I used had been in a pile of distributors outside on a shelf under my patio roof for years.
You need to remove this gear from you 320 distributor(it's a bitch, has solid pin).
or from your J13(a lot easier, dowel type pin)
then you need to remove the gear from the Matchbox distributor.
, Now you put the 320 E1 or J13 drive gear on the matchbox, I also used the J13 mount bracket, I believe that is the easiest one to modify.
This is Mikes photo, you have to file this hole open a little on the J13 mount bracket to fit it to the matchbox housing, I also cut the other end of the bracket off just past the other oblong hole.
You can see where I cut it in this photo.
This is what the plate looks like mounted on the block, you can also see better how I cut it.
OK before you put the dowel pin in your going to have to buy one at the hardware store as the solid pin I hammered out got ruined as it did not want to come out, and the dowel pin for the matchbox gear is too short, you are going to have to orient the drive gear in the correct position on the shaft, standing at the side of the engine you want the rotor pointed at around 2pm with the vacuum advance pointed the same direction, around 2pm, you can also see in the photo below that the matchbox gear pointers inside the distributor are aligned.
The small side of the drive gear will be towards the front of the engine, by the way your engine should be at TDC.
The mounting plate needs to have the oblong hole pointed towards 2pm also, this is the bolt that mounts the plate to the distributor.
Now if the plate is on correctly, the rear oblong hole will be towards the rear of the engine, and that is the hole used to mount the distributor to the engine.
Now if everything has been done correctly, the top front spark plug hole on the cap is number one, the firing order is 1, 3, 4, 2 counter clockwise.
Now you also need an electronic ignition coil, and I repeat, this is a negative ground setup.
I will update this post when I think of things I should have put in the post, or when you good folks point out something I have forgotten.
OK, this is how I did it, first you need a matchbox distributor from an L block(Hitachi D4K) from a 1979 Datsun 620 or a 1980 Datsun 720, and you need your E1 or J13 series distributor, there are likely other L block cars that had the matchbox also.
The Matchbox I used had been in a pile of distributors outside on a shelf under my patio roof for years.
You need to remove this gear from you 320 distributor(it's a bitch, has solid pin).
or from your J13(a lot easier, dowel type pin)
then you need to remove the gear from the Matchbox distributor.
, Now you put the 320 E1 or J13 drive gear on the matchbox, I also used the J13 mount bracket, I believe that is the easiest one to modify.
This is Mikes photo, you have to file this hole open a little on the J13 mount bracket to fit it to the matchbox housing, I also cut the other end of the bracket off just past the other oblong hole.
You can see where I cut it in this photo.
This is what the plate looks like mounted on the block, you can also see better how I cut it.
OK before you put the dowel pin in your going to have to buy one at the hardware store as the solid pin I hammered out got ruined as it did not want to come out, and the dowel pin for the matchbox gear is too short, you are going to have to orient the drive gear in the correct position on the shaft, standing at the side of the engine you want the rotor pointed at around 2pm with the vacuum advance pointed the same direction, around 2pm, you can also see in the photo below that the matchbox gear pointers inside the distributor are aligned.
The small side of the drive gear will be towards the front of the engine, by the way your engine should be at TDC.
The mounting plate needs to have the oblong hole pointed towards 2pm also, this is the bolt that mounts the plate to the distributor.
Now if the plate is on correctly, the rear oblong hole will be towards the rear of the engine, and that is the hole used to mount the distributor to the engine.
Now if everything has been done correctly, the top front spark plug hole on the cap is number one, the firing order is 1, 3, 4, 2 counter clockwise.
Now you also need an electronic ignition coil, and I repeat, this is a negative ground setup.
I will update this post when I think of things I should have put in the post, or when you good folks point out something I have forgotten.
Last edited by wayno on Tue Feb 07, 2017 8:20 pm, edited 2 times in total.
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Re: Electronic Ignition upgrade for your 320
Good write up.
When the only tool you have is a hammer every problem starts to look like a hippy.
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Re: Electronic Ignition upgrade for your 320
Thankyou, does it make sense, is there anything I left out, as I might have taken it for granted that everyone knows what I know about parts?DRIVEN wrote:Good write up.
I am no writer, so if you guys think I left something out tell me and I will edit the post, I want it to be fairly easy for someone else to do this by reading the post, Mike did this also, but he does everything too like new condition, so there are extra steps in his NL320 thread about this, I just took two distributors and made one without cleaning everything up, I was surprised it worked so good.
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Re: Electronic Ignition upgrade for your 320
I can hardly believe all the crap I have went thru with the stock 320 distributors over the last few years, especially with all the options out there.
Today I decided since no one has called me about my MG Midget engine(1500 Triumph engine) I was going to tear it down and get it out of my way, I was going to save all the parts I thought might work on something else, especially the new Weber carb on it, well I pulled the electronic distributor and looked at it, the drive gear looked like a 320, but the pedestal was wrong but removable, so I took it off and it looked just like a 320 distributor, I had a 320 dist. in a parts box so I took the mount bracket off it and installed it on the MG distributor and it fit perfect, so I checked the distributor shaft length and it was exactly the same, so I decided to pull the 320 dist. out of the truck again and see if this fit.
It fit perfect and is 360 degree adjustable like the stock 320 distributor, so I pulled all the wires again to make it run on negative ground and wired it all up again to run, this engine is stone cold, I pumped the pedal 3 times, pulled the choke on, made sure it was in neutral, moved out front, powered the coil, hit the starter trigger and the damned thing started right up and ran great, I timed it and just like the matchbox dist. above, the engine ran way better than with the stock 320 distributor, and what is awesome about this is that it is a bolt in with the stock Datsun 320 mount bracket.
There is one drawback about this electronic ignition, it is an aftermarket Jacobs Electronic Ignition, it is a very complicated setup, but there are other MG Electronic Ignitions out there that could likely be exactly the same except way less complicated wiring wise, here is a photo of all the crap that came with this high performance system, I am lucky I ever got it to run with so many wires to sort out.
Every distributor I put in this engine works better than the stock distributor, what's cool about this EI dist. is that it was a bolt in using the 320 dist. mount bracket, there is nothing to change, the drive gear is exactly the same as the 320 drive gear.
I wonder if all of that crap could be replaced with a GM Module?
Today I decided since no one has called me about my MG Midget engine(1500 Triumph engine) I was going to tear it down and get it out of my way, I was going to save all the parts I thought might work on something else, especially the new Weber carb on it, well I pulled the electronic distributor and looked at it, the drive gear looked like a 320, but the pedestal was wrong but removable, so I took it off and it looked just like a 320 distributor, I had a 320 dist. in a parts box so I took the mount bracket off it and installed it on the MG distributor and it fit perfect, so I checked the distributor shaft length and it was exactly the same, so I decided to pull the 320 dist. out of the truck again and see if this fit.
It fit perfect and is 360 degree adjustable like the stock 320 distributor, so I pulled all the wires again to make it run on negative ground and wired it all up again to run, this engine is stone cold, I pumped the pedal 3 times, pulled the choke on, made sure it was in neutral, moved out front, powered the coil, hit the starter trigger and the damned thing started right up and ran great, I timed it and just like the matchbox dist. above, the engine ran way better than with the stock 320 distributor, and what is awesome about this is that it is a bolt in with the stock Datsun 320 mount bracket.
There is one drawback about this electronic ignition, it is an aftermarket Jacobs Electronic Ignition, it is a very complicated setup, but there are other MG Electronic Ignitions out there that could likely be exactly the same except way less complicated wiring wise, here is a photo of all the crap that came with this high performance system, I am lucky I ever got it to run with so many wires to sort out.
Every distributor I put in this engine works better than the stock distributor, what's cool about this EI dist. is that it was a bolt in using the 320 dist. mount bracket, there is nothing to change, the drive gear is exactly the same as the 320 drive gear.
I wonder if all of that crap could be replaced with a GM Module?
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Re: Electronic Ignition upgrade for your 320
Good info.
Been a while since I've seen a Jacobs box.
Been a while since I've seen a Jacobs box.
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Re: Electronic Ignition upgrade for your 320
There are 2 boxes and a shit load of wires, and they go everywhere, and there is a toggle switch coming form the energy box with 3 positions, so far it only runs in two of the positions, maybe the middle position is a kill switch, there are just way to many wires, I went out and took photos of the boxes, here they are, can I get rid of either of these boxes?DRIVEN wrote:Good info.
Been a while since I've seen a Jacobs box.
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Re: Electronic Ignition upgrade for your 320
What type of trigger is in the distributor? That Crane box is supposed to be for an optical trigger. Not sure about the Jacobs. If the distributor has a magnetic trigger then I would think you can use an HEI module.
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Re: Electronic Ignition upgrade for your 320
Can you tell from either of these photos what type it is, I don't feel like removing it right now.
Is the HEI module the GM one?
Is the HEI module the GM one?
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Re: Electronic Ignition upgrade for your 320
Yeah, HEI is GM.
You have an optical pickup. By the looks of this diagram http://www.cranecams.com/uploads/instru ... -0700_.pdf (figure 20?) you should be able to eliminate the Jacobs box and related wiring if you want to simplify the wiring.
You have an optical pickup. By the looks of this diagram http://www.cranecams.com/uploads/instru ... -0700_.pdf (figure 20?) you should be able to eliminate the Jacobs box and related wiring if you want to simplify the wiring.
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Re: Electronic Ignition upgrade for your 320
One of those diagrams says this can be used as positive ground, that is freaking great as that is what this truck is right now.
Thankyou for finding that info for me, I searched and searched for anything on this Jacobs EI setup, I didn't think to search Crane, thankyou again, this is great.
Thankyou for finding that info for me, I searched and searched for anything on this Jacobs EI setup, I didn't think to search Crane, thankyou again, this is great.
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Re: Electronic Ignition upgrade for your 320
No sweat. Hope it works out for you.
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Re: Electronic Ignition upgrade for your 320
I deleted the Jacobs energy module, I took it apart in such a way as I could have put it back on, but it runs fine without it, what is it for?
So now all them wires are gone, but it is still wired negative ground, but I seen a tech number and I called it, it's a good number, but there hours are 9-5 eastern, and it was 4:50 pacific when I called, I will call tomorrow morning and ask if I can wire the XR3000 positive ground like the XR700.
So now all them wires are gone, but it is still wired negative ground, but I seen a tech number and I called it, it's a good number, but there hours are 9-5 eastern, and it was 4:50 pacific when I called, I will call tomorrow morning and ask if I can wire the XR3000 positive ground like the XR700.
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Re: Electronic Ignition upgrade for your 320
I don't know for a fact but I think the Jacobs box acts like an MSD giving multiple strikes up to a certain RPM. Probably has variable dwell too and I seem to remember reading that it retards timing at cranking RPM for easier starting. Again, don't quote me on it.
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Re: Electronic Ignition upgrade for your 320
I will have to more about it before I put it back on.
I did notice when I first put this on the engine that when I was trying to time it that it kinda was jumping around, so I just now went out and stuck the timing light on it, and it seems to be rock solid now.
What do you think that 3 position switch on the Jacobs module was for?
The middle position killed the engine, but the two other positions it would run.
I did notice when I first put this on the engine that when I was trying to time it that it kinda was jumping around, so I just now went out and stuck the timing light on it, and it seems to be rock solid now.
What do you think that 3 position switch on the Jacobs module was for?
The middle position killed the engine, but the two other positions it would run.
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Re: Electronic Ignition upgrade for your 320
I found a posting with a Jacobs box for sale that referenced the switch. Apparently 1 position bypasses the Jacobs box and runs on the primary ignition system alone, the middle should disable the ignition like a kill switch, and the other position piggybacks the Jacobs to the primary ignition.
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Re: Electronic Ignition upgrade for your 320
OK, I took a real close look at the switch, one side says "CONV. IGN", the other says "COMPUTER", but it is very beat up and I don't see so good anymore.
My search skills are also not so good, as I did search it and came up with nothing, I tried again and didn't find anything useful although I found a lot more this search.
If I put it back on I will do it differently, all them stupid wires on the coil is ugly and back yard mechanic looking, but first I need to make the call to the tech line and see if this Crane XR3000 module can be wired positive ground.
My search skills are also not so good, as I did search it and came up with nothing, I tried again and didn't find anything useful although I found a lot more this search.
If I put it back on I will do it differently, all them stupid wires on the coil is ugly and back yard mechanic looking, but first I need to make the call to the tech line and see if this Crane XR3000 module can be wired positive ground.
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Re: Electronic Ignition upgrade for your 320
OK, I took a couple chances today, first I wired up a matchbox distributor on the bench normally and got it working, then I tried wiring it positive ground every way I could think of and could not get it to throw a spark, and I tried a lot of ways, good thing is that I didn't smoke it either.
My second chance was to get out the MG Midget electronic ignition optical triggered distributor, wired it up normally and it worked fine on the bench, then I wired it for positive ground on the bench like the instructions said to do for the XR700 Crane module that Driven posted a link to, even though I have the XR3000 Crane module and it worked, it is kinda confusing as the black ground wire is connected to the ignition switch, and the positive side of the coil is grounded to the body.
Anyway it worked on the bench, so I pulled the stock 320 distributor out and put the MG Midget electronic ignition optical trigger distributor in, I wired it for positive ground, I wrapped a rag around the coil so it was not touching any metal just in case, got in the truck and it started right up, now one really confusing thing is that the black wire coming from the Crane XR3000 control box goes to the ignition switch only, it does not go to the coil, the positive coil side goes to ground and the control box(red wire), the negative side of the coil goes to the control box(yellow wire), and if you want a tach, your supposed to use the black ignition wire that goes to the fuse block, very strange.
So I successfully wired an electronic ignition(optical type trigger) to a stock positive ground Datsun 320 with generator using a MG Midget electronic ignition(optical trigger type) made by Crane Cams Ignition, and they may still sell this type of electronic ignition distributor, at least that is what it sounded like when I was talking to them on the phone.
So here it is mounted.
Here is the control module behind the battery, the mount tabs are plastic, it is not grounded to the body.
And here is the coil, it says "No External Resister Needed", not sure if the control module is going to like that, I will check the coil for heat, if it gets hot, I will install a ballast resister, oh and I tested the coil housing while the engine was running by grounding it out to the body, no sparks, so I used the coil already in the truck this last time.
I am leaving it this way this time, as I changed nothing in the wiring harness this time, I am hoping this works long term.
My second chance was to get out the MG Midget electronic ignition optical triggered distributor, wired it up normally and it worked fine on the bench, then I wired it for positive ground on the bench like the instructions said to do for the XR700 Crane module that Driven posted a link to, even though I have the XR3000 Crane module and it worked, it is kinda confusing as the black ground wire is connected to the ignition switch, and the positive side of the coil is grounded to the body.
Anyway it worked on the bench, so I pulled the stock 320 distributor out and put the MG Midget electronic ignition optical trigger distributor in, I wired it for positive ground, I wrapped a rag around the coil so it was not touching any metal just in case, got in the truck and it started right up, now one really confusing thing is that the black wire coming from the Crane XR3000 control box goes to the ignition switch only, it does not go to the coil, the positive coil side goes to ground and the control box(red wire), the negative side of the coil goes to the control box(yellow wire), and if you want a tach, your supposed to use the black ignition wire that goes to the fuse block, very strange.
So I successfully wired an electronic ignition(optical type trigger) to a stock positive ground Datsun 320 with generator using a MG Midget electronic ignition(optical trigger type) made by Crane Cams Ignition, and they may still sell this type of electronic ignition distributor, at least that is what it sounded like when I was talking to them on the phone.
So here it is mounted.
Here is the control module behind the battery, the mount tabs are plastic, it is not grounded to the body.
And here is the coil, it says "No External Resister Needed", not sure if the control module is going to like that, I will check the coil for heat, if it gets hot, I will install a ballast resister, oh and I tested the coil housing while the engine was running by grounding it out to the body, no sparks, so I used the coil already in the truck this last time.
I am leaving it this way this time, as I changed nothing in the wiring harness this time, I am hoping this works long term.
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Re: Electronic Ignition upgrade for your 320
I ordered two different distributors today for the 320 E1, and the 520 J13/15 engines, I ordered this because it has a side entry for the plug wires like the U320 has, and the clearence is very tight because of the steering column, so I cannot use any other type of distributor cap.
http://www.ebay.com/itm/MG-Midget-1275- ... 7w&vxp=mtr
This one I ordered is electronic ignition and normal negative ground, the truck has been changed to negative ground already by a previous owner, it has a British alternator on it now, so I am hoping this truck will start easier also, it is just as hard to start as my L320 was, as it has a stock 320 distributor like the L320 had, I really dislike 320 distributors, this new distributor should bolt right in using the stock 320 mount bracket.
The other one I ordered is a used Triumph/MG Midget 1500 original Lucus 45DE4 distributor with a XR700 Crane ignition, this one has the same type ignition module that my L320 has that is positive ground except mine is an XR3000, but the literature I read said the XR700 could be used positive ground, so I bought it just in case I put the U320 back to positive ground someday, it was cheap.
320 ignition parts are hard to find, and these MG Midget/Triumph parts are bolt in parts, and they have aftermarket parts available, I am surprised no one else thought of this before now.
http://www.ebay.com/itm/MG-Midget-1275- ... 7w&vxp=mtr
This one I ordered is electronic ignition and normal negative ground, the truck has been changed to negative ground already by a previous owner, it has a British alternator on it now, so I am hoping this truck will start easier also, it is just as hard to start as my L320 was, as it has a stock 320 distributor like the L320 had, I really dislike 320 distributors, this new distributor should bolt right in using the stock 320 mount bracket.
The other one I ordered is a used Triumph/MG Midget 1500 original Lucus 45DE4 distributor with a XR700 Crane ignition, this one has the same type ignition module that my L320 has that is positive ground except mine is an XR3000, but the literature I read said the XR700 could be used positive ground, so I bought it just in case I put the U320 back to positive ground someday, it was cheap.
320 ignition parts are hard to find, and these MG Midget/Triumph parts are bolt in parts, and they have aftermarket parts available, I am surprised no one else thought of this before now.
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Re: Electronic Ignition upgrade for your 320
I believe this is a bolt in for a 320 positive ground truck using the stock 320 mount bracket.
http://www.ebay.com/itm/Pertronix-D1786 ... Lg&vxp=mtr
http://www.ebay.com/itm/Pertronix-D1786 ... Lg&vxp=mtr
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Re: Electronic Ignition upgrade for your 320
It was brought to my attention by Andy this morning that the equivalent of the Datsun 320 E1 distributor mount/clamping plate is available at Moss Motors to this day(part #153-400), they can be bought brand new.
Here is a link to that part, it is part #21 in the diagram.
http://www.mossmotors.com/Shop/ViewProd ... exID=29249
This can be used on the Datsun 320 E1 distributor and likely the J block also to mount a 320 distributor or better yet an electronic ignition MG/Triumph distributor in your Datsun 320/520, it will not work on the J block distributor or the Matchbox distributor.
Here is a link to that part, it is part #21 in the diagram.
http://www.mossmotors.com/Shop/ViewProd ... exID=29249
This can be used on the Datsun 320 E1 distributor and likely the J block also to mount a 320 distributor or better yet an electronic ignition MG/Triumph distributor in your Datsun 320/520, it will not work on the J block distributor or the Matchbox distributor.
“The difference between genius and stupidly is that genius has its limits” Albert Einstein