I am installing DLDFIS (asp. Jeff20b article). I have manufactured the J109 ignintors grounding plate. Now I am addressing the coils to use in the retrofit?
1. Can factory 84 RX7 coils be used?
2. Can MSD DIS Racing Coils be used?
3 . What are the factors in concidering coil selection?

 

From many previous posts, it looks like most people use either stock diamond coils or MSD Blaster 2 coils. However, seems like Accel and other brand coils have also been used. The only real criterion is that you use matching coils for the leading plugs. If you have 3 diamond coils, use em. If you only have 2, use 2 for the leading, and get another quality one for the trailing. Hope that helps.

 

Got your message, Sorry i had exams last week and didn't make it to the Post office, the ignitor will be in the mail this week.

good luck with the direct fire system, I used 2nd gen stock coils on my 83...very cheap and very effective....

 

So, can I use the MSD DIS Racing coil? They look small and will conserve space, also relatively cheap $45 bucks a pop. I can't seem to find the diamonds.
Thanks

 

Some of thos MSD coils are meant to be used only with MSD ignitions! They will not fire very well when used with stock ignition. Also, you can pick up blaster 2 coils at autozone for 40 bucks, they fit in stock locations and make just as much power.

 

You guys are on top of things here. Just be aware, as Xavier said, that some MSD coils work best with MSD CDI products, such as the MSD 6A. Off the top of my head, I don't know which aftermarket DIS coil will work with a single J-109 ignitor. I don't think it would be a good idea to hook the C(-) terminals of the J-109s together to fire a DIS coil.

Maybe somebody around here has a 2nd gen leading coil with ignitor base they let go for cheap? That can work with the stock FB dizzy's pickup if I believe the red wire is grounded. I'm learning about this 2nd gen stuff right now, so I don't know for sure yet.

Anyway, Diamiond, Bosch, Hanshin; it's all good. The Bosch and Hanshin are OE replacements for the Diamond coils and are probably similar in price to the Blaster II coils, and can be found in auto parts stores. I've only ever used Diamond and Bosch coils personally, so I don't know how well the Blaster IIs will perform on J-109s. No wait, I do have one Hanshin in my MG on trailing. I also have another spare Hanshin and Bosch sitting here for other projects. You'll have to ask others who've used Blaster IIs with J-109s.

 

Wow, I hooked up my 2nd gen leading coil today for my direct fire setup, and while playing with the timing pulley by running the starter, the engine was trying to start with just the gas put into it from earlier when I tapped the accelerator pedal and the accelerator pump put some gas in the engine. The fuel pump wasn't even hooked up! She's gonna start and run nice if my streetport RB holley ever comes in. More impressions to come, but just wanted to say a 2nd gen leading coil works at least fired off a J-109.

 

Therefore, any standard distributor coil can be used, provided it creates enough voltage. So I can use my 2 spare junker coils.

 

Xavier, you're going to use the ballast resistor that comes with the 2nd gen coil, right?

magnanimus, basically yes. They're not points coils are they?

 

82 RX7 coils, the same coils that use the J109 pickups. I believe that would be the electronic type coil? Im a amateur when it comes to electricity.

 

Yes, I did wire in the ballast resister in the circuit of the 2nd gen coils. Didn't want to fry any ignitors.

 

I have the 2nd gen leading coil setup on my car. I have a 1980 so the stock ignition box on the fender was actually a GOOD thing in this case. I used the ballist resistor on my setup. I have gone approximately 3000 miles on this setup. No problems and I am using the 1980 ignitors. I am considering trying a j-109 ignitor just for giggles. I know it is shorter but one screw hole lines up and connects properly. The next thing I may try are the GM ignitors so I will be asking you some questions in the future.

Honestly, I don't know the advantage of having the other setup. The two stock or MSD coils...

 

Xavier8,

So, you are using two, FC leading coils with two leading ignitors? Or are you using two leading ignitors with two trailing coils? What schematic are you using for your setup?

Does anyone have the pinout for the trailing ignitor? It has a bunch of pins on it, and perhaps it has two distinct outputs to drive each coil seperately? Or does it fire each coil simultaneously?

Also, i wonder why there is no ballast resistor within the trailing ignitor? Does it use an external resistor that can be bypassed for starting, then active for running?

 

To answer your question, you cannot fire both trailing plugs at the same time. It's very bad for the engine.

Here is a thread where a guy is discussing the 2nd gen stuff with me. http://www.nopistons.com/forums/inde...howtopic=40326

 

According to him, it's ok to leave the ballast resistor out of the circuit if you'r hooking up a 2nd gen trailing coil to a 2nd gen leading ignitor because the trailing coil has more resistance. He also said the leading coil has the least resistance of any coil he'd ever tested.

I think the final word is the ballast resistor is not needed if hooking the 2nd gen leading coil to an MSD. It's also not needed if hooking a 2nd gen trailing coil to a 2nd gen leading ignitor. It's only needed if using the 2nd gen leading ignitor, or a J-109, with a 2nd gen leading coil. Can anyone confirm that I'm 100% correct?

 

That seems to be what I found. I am running a single leading coil fired by a J-109 ignitor. The ballast resister is connected in the circuit. The leading coil has two outputs, one for each leading plug. Very easy direct fire setup, used the original wiring harness, just had to solder some of the connections together. I do now have a leading 2nd gen ignitor, might be willing to give it up to science.