Ignition Nitty-Gritty

[ToastyBass]

Heyo Ratsun,

 

RockAuto doesn't like Cali cars. According to my service manual, the Cali-spec ignition system on the '75 B210 (Electronic Ignition) requires a Primary Res. 0.45-0.55 Ohm Coil. 

 

I'm not finding that for a decent price online. I'm here to ask: what is the spec primary resistance of an '81 B310 coil? I have an '81 parts car with the epic matchbox-distributor and want to know if a standard NGK coil reading about 1.4 ohms will work on that matchbox. I have reason to believe my Fed-spec coil in question is the cause of my misfire issue that has plagued the car since I began ownership.

 

Could it be my Hitachi E12-08 Ignition Module? Possibly, but I doubt it. It's gotten uncomfortably warm during running, even for only 5 seconds or so. That leads me to suspect the coil. (increased effort due to 3x the recommended resistance) The harness tested just fine, and individually measuring the segments of my 4-post ballast resistor also check out as OK.

 

To sum up:

- Matchbox + 1.4 ohm coil = okay?

- Can anyone find an affordable IGN coil < 0.6 ohms?

Edited October 17, 2023 by ToastyBass

[datzenmike]

I can't believe that's correct. 0.45- 0.55 ohms???? seems very low. That's a Nissan factory service manual???

 

All matchbox distributors use a 0.75-.1.0 ohm coil. If you have a 1.4 ohm coil it may be from a points distributor and it will run very hot. Not good for it. Any coil after '77 will be EI and 0.75-1.0 ohms.

 

[ToastyBass]

That is indeed what it tells me, I find it bizarre too! Sure as the sky is blue, it's an original service manual. It's the most detailed thing I have when compared to everything online, especially the CA IGN wiring. That's good to know about all matchboxes, thank you.

Guess I won't be going to RockAuto, they keep using the same NGK coil across several model years, way into the EI era...

(Or maybe my coil is just bad and I'm a lil stupid. If anyone would be able to confirm, it's NGK 48776)

[datzenmike]

Nissan coils are Hitachi.

 

I know that an earlier version of the EI was use on California emissions engines starting in '76? and it has a ballast with 4 wires to it. The lower coil resistance may only be for hotter spark when starting and combined with ballast for running.

[ToastyBass]

My lil' Coupé was made in Nov. of '74 according to my door placard, making it a '75 M/Y. (but my OG trans isn't a 5-speed...) I don't disagree about the 4-post resistor, I had to rewire it back to factory spec when I got the car! You're right about the lower resistance for starting and full for running, but the coil's spec is that weird <6 ohms. I've attached some .PDF scans to see for yourself. 

p. 1 is for validity

p. 2 is to show the testing procedure for the coil assembly (which it failed)

p. 3 is a diagram of my circuit (with the Cali resistor)

And p. 4 is the IGN coil page listing the goofy specs

 

If anyone wouldn't mind linking a snazzy coil that matches up these specs OR would work with a matchbox from '79 on, that'd be much appreciated.

Datsun B210 EE Section Sample.pdf

Edited October 18, 2023 by ToastyBass

[datzenmike]

A higher resistance coil should still work just not as hot a spark when starting. Obviously California switched to regular EI in '78.

[ToastyBass]

I'm getting an idea that I don't really like.
Z Car Depot has a coil they sell for all S30 Z's '70-'78 (EI included) that's labeled as "Internal resistor."

I'm pretty sure I could do that with my NGK coil and the matchbox, but is it possible for that early IGN module?...

 

Even looking at B310 service info, they say the primary res. on its coil is 0.8-1.0 ohms, which is still less than what I got.

Seeing as my options for affordable factory-spec are slim, what do you think?

(side note: if I had continued scrolling I would've seen the Pertronix Flamethrower II, which would work. $60 for a coil seems a little crazy though)

Edited October 18, 2023 by ToastyBass

[datzenmike]

Points coils are over 1.2 ohm likely 1.5 and have to had a 1.5 ohm ballast resister in line so the total ohms is around 4.

 

EI coils can be 0.75-1.0 ohms and no ballast. The lower ohms allows more current flow through it making a hotter spark. The EI modules can easily handle this current. If a points coil 1.5 ohms is used with an EI distributor it will allow twice the designed current through it and over heat. You can run a points coil in an EI system if you use a ballast resistor, but now the hotter spark is lost.

 

As to the early California EI set up I have no idea if it's the same spec as the '78 and up EI.

[banzai510(hainz)]

I would just run the TRY the .7 ohm Coil from the 78/79 year and install it to your system. Spark might be a little less.

 

if you think maybe coil is bad rn it at night maybe youll se a SPARK arch across something.

 

look close at ballast resisitor under neath to see if moisture rotted the wire. clean connections.

 

I have never had a coil go bad myself.If wired correctly

[ToastyBass]

Good news!

 

Summit has a coil with PR 0.45 ohms! AND it's $30 (instead of $60)

Summit Racing SUM-850496 Summit Racing™ High-Output Ignition Coils | Summit Racing

 

I'll install it with the original Cali IGN and report how it goes.

 

[ToastyBass]

Just realized I never did update this, so here goes.

 

Works GREAT. After taking apart my 4-post Cali resistor, cleaning, and reassembling with conductive grease, spark is great!

Didn't even need to install that matchbox dizzy from the '81. (TBH, willing to sell. PM for interest, you pay shipping and it'll go anywhere)

Sadly I burn so much oil that clean plugs are fouled within 5 minutes...

 

But again, cleaned plugs and it idled the smoothest it ever has since I bought it.

[nathan.is.an.idiot12312]

i highly suggest you invest in a haynes manual for your car off of ebay, has all the info you wont find online and lots of tips and lists of tools youll need for the car

[nathan.is.an.idiot12312]

also torque settings for literally everything

[datzenmike]

35 minutes ago, nathan.is.an.idiot12312 said:

i highly suggest you invest in a haynes manual for your car off of ebay, has all the info you wont find online and lots of tips and lists of tools youll need for the car

 

 

Ehhhh I'm never impressed with Haynes. If a manual for the B-210 it will try to cram every year '74-'78 B-210 made into 1/2" thick book. Go to e-Bay and find a '75 factory service manual FSM for your B-210. EVERYTHING in it is for YOUR year car. You don't need to know how to rebuild the optional FS5W63A 5 speed in the '77 and on  car. The FSM is about 2" thick with everything you could want to know about working on your B. $30-$60 with luck $20

 

https://www.ebay.ca/itm/352616240702

 

https://www.amazon.com/-/es/Nissan-Motor-Co/dp/B000BKICTA

 

 

 

Generally it pays for itself the first time you use it.

[nathan.is.an.idiot12312]

5 hours ago, datzenmike said:

 

 

Ehhhh I'm never impressed with Haynes. If a manual for the B-210 it will try to cram every year '74-'78 B-210 made into 1/2" thick book. Go to e-Bay and find a '75 factory service manual FSM for your B-210. EVERYTHING in it is for YOUR year car. You don't need to know how to rebuild the optional FS5W63A 5 speed in the '77 and on  car. The FSM is about 2" thick with everything you could want to know about working on your B. $30-$60 with luck $20

 

https://www.ebay.ca/itm/352616240702

 

https://www.amazon.com/-/es/Nissan-Motor-Co/dp/B000BKICTA

 

 

 

Generally it pays for itself the first time you use it.

hell yeah thanks for the tip, had no idea i could get those

[nathan.is.an.idiot12312]

well would ya look at that, i found it for free!

 

https://www.zonedatsun.fr/wp-content/uploads/2018/03/TECHNIQUE-DATSUN-210-USA-type-310-A12a-A14-A15-1981.pdf

[datzenmike]

There ya go.