Last night, my buddy and I embarked on the path of direct fire.

It was a very painless process, taking about two hours to complete, including a trip to my apartment to get some nuts for the ignition coils.

Because I have a '79, and had already swapped in an '81 distributor, I had a custom harness for the ignitors that I reused for the dual leading ignitors. Plug and play. For the coils, my dad and I manufactured a mounting bracket out of aluminium that mounts to the strut tower, so wiring up the coils was a snap. I mounted the ignitor plate where the coils used to be and got rid of a boatload of useless wires left over from the old ballast resistors. For the trailing, I made a new set of wires and incorporated the bullet plug from the dizzy. I followed the basic diagram on Jeff20B's site, and it worked quite fine for me. Having a wiring diagram is very usefull as well.

After we were done, I hit the key and she fired right up. There was a small difference in the sound of the motor, and my butt dyno thinks that there is a little more power. The only snag is the idle. Before the conversion, my idle fluctuated a bit, and now it fluctuates quite a bit more. I would suppose it's a vaccuum leak, so I'll have to track that down.

I am also wondering how those of you that have done this conversion have worked out how to get the connectors from the leading ignitors to stay in the leading magnetic trigger securely. There seems to be alot of slop in the plug, so I taped the connectors to it, but it's still flimsier than I would like. I used a medium U

All in all, I'm quite happy with the whole system so far, and I'll take some pics tonight of the setup.

 

Get a bad igniter, gut it and use that as a junction box. If you find the old connector for the sub zero assist, you can cut it off (leave enough wire to splice it into your new harness). That'll give you a connector that will fit in the top of the igniter.

 

Yes. Carl's method was used on my DLIDFIS setup, and also used Jeff20B's process. I plan on augmenting Jeff20B's write-up with our pictures/parts sometime in the not-too-distant future. Of course, I've been saying that for a few months now...

 

That's cool that you got it to work on your 7 rather painlessly. I personally haven't hooked up a 7 yet, as all my vehicles are pre-RX-7, or previously piston powered, so I can't give any specific details about them.

My REPU was similar to a '79 car because I too upgraded from points to an FB dizzy before taking the direct fire plunge.

Two things to help you out. First, you might want to hook up a relay to feed your coils and ignitors from the battery directly, instead of having to torture the stock ignition switch wires with all the extra, uh juice. It also reduces voltage drop to everything. It also elliminated a blip at idle that I used to get from time to time. Second, I've found the little quick disconnects from car stereo shops make great connectors for the pickup tabs on the back of the ignitors. Tweeters typically use this size. They're too tight, so I tweak them open with a small screwdriver before use. For the pickups themselves, I've also used a dead ignitor that's been jumpered inside.I've also had good results with filed-down male quick disconect tabs. They're a little thick so they won't fall out. So far so good.

RMD's writeup was pretty good because it had lots of 7-specific info. I'm sure pratch's writeup will be good too. Now start typin'!

 

When you get the ignitors from the junkyard, grab the dizzy's red and green wires too.

 

I'm fairly clueless when it comes to this electrical stuff, I do well with good directions and the factory diagram, but I'm a little hazy on what's required to wire up a relay to the battery. Could you elaborate?

I followed your advice and got the quick disconnects for the ignitors, and they worked quite well for both the back plugs and the top plugs. I am using fairly small spade connectors for the trigger, so I guess I'll take those off and try a larger connector.

So far, the car is running good, and I think that it's more powerful throughout. Not outstandingly so, but just enough to notice. Next on the list, finally installing my '81 rear axle and getting rid of my emissions so I can install my RB header.

 

As promised, here are the pics of my install. I re-did some of the connections, cleaned up some of the old wires and put some blue loom onto the major wires. I realized that I forgot to wire in the condensor on the dizzy to the trailing ignition, so I did that, and my idle was noticeably improved.

Thanks to Jeff20B for his thoughts and write up. Hopefully between his original write-up, RMD's write up, and my modest contribution, anyone can do the DLIDFIS conversion without incident.

 

That's really cool!

Ok, about the relay. It only has four tabs. One goes to ground. One goes to the key switch. The other two are straight through. They bridge the gap between the battery and the ignitors and coils and can handle 30 amps or whatever the rating is.

 

Do you think it would be wise to put a fuse or fuseable link between the battery and the relay and if so what size would be appropriate?

Oh... and is there any reason why you couldn't power both the leading and trailing coils with the relay?

 

Use a 20 amp fuse or anything that won't get blown by normal use. All a fuse does is protect the battery incase the wire falls off and shorts to ground or anything else that could happen to cause a short.

All my ignition components are fed with a relay. Ignitors, coils, T and L, everything.

 

Just a followup to this thread, my setup has a couple of thousand miles on it now, and it still works great. The ignitors barely got hot to the touch in the summer, and now that we've descended to below freezing temperatures, they don't even warm up. My car starts right up in the cold, much better than it did last winter, and it is easier to drive when not fully warmed up. (Slowly and light on the throttle of course!) All in all, I'm very pleased with this mod, it has produced some real and appreciable gains.

 

Just a quick question guys. I have someone who can install a DLIDFIS setup in my car. Is that a good idea for a daily driver that I'm building for reliability?

 

My car is my daily driver and it has given me ZERO problems in the last three months. It drives better no the street and on the autocross course because of this mod. I really can't praise it enough.

 

There are no known disadvantages to a DLIDFIS setup under any condition in my opinion. Especially for a street car because it improves low/mid range RPM flexibility of the engine, not to mention it also shines at the top end.

 

Slightly off topic...

Would you need DFLIDS (or whatever)

If you are running two seperate MSD 6AL Boxes
and two MSD Blaster 2 Coils?

I am curious, as I am finishing my ignition now.

 

I think you should make a Step by Step Tutorial in how to do this for those that have a bloody clue about rx7 like my self. LOL!

 

Courtesy of Jeff20B -

http://www.geocities.com/cd23c/dlidfis.html

 

Haha nice Thanks

 

im not good with the whole elctronics part of cars, even with the turorial i am still a bit confused...o well looks like i will have to do some research..like i see 3 coils but only 2 ignitors??? just stuff like..mayby im just dumb but i read the tutorial and it still doesnt make total sense to me

 

and where is the trailing ignitor mounted?

 

the trailing stays on the dizzy where it was before

 

Now that I have access to a digital camera, I think I'll take a few pics for the noobs.

 

Not to say that I am a total noob but....I do love pics on tutiorials. But I am a visual (and even then kinda stupid) person.

 

Well, I know TheLatinHeat is interested in some more info. I'll get some pics of my white REPU's setup. Then if there's time, I'll shoot some of my other projects.

 

ok well i think i am starting to get it i took like 3 hours today and figured out the whole process... the only thing i dont understand is where the wires from the leading ignitors go? do they go in the spot where the single one was mounted on the dizzy before? if so then i should have it figured out

p.s. are the j109 ignitors just the stock ignitors or do you have to get them from a part store or a junk yard?