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-   -   EASY 2nd gen direct fire install - 20 minutes (https://www.rx7club.com/1st-generation-specific-1979-1985-18/easy-2nd-gen-direct-fire-install-20-minutes-243350/)

Jeff20B 03-31-05 02:09 PM

Here is a quote of one of my posts on page 8 of this thread:

I'm glad somebody brought this thread back up because I'd like to let everyone know they should keep the 2nd gen ignitor. There is a way to trigger it from your J-109 with a transistor circuit. It's a whole lot more powerful. I'm going to look into how to do it after I finish my current projects. Please everyone, keep your 2nd gen ignitors intact. Don't even remove them from the base. Simply bypass it for now since the ballast resistor is required for the J-109, and all that.

Anyone is welcome to attemp the transistor trick. I don't know enough about it to even attempt to explain how it works other than it allows the J-109 with its variable reluctance sensing and dwell capability to control the 'dumb' 2nd gen leading ignitor, which lacks the ability to correctly read the output of the 1st gen style pickup (VR sensor). The 2nd gen stuff was designed to trigger from a 5 volt square wave from an ECU. I've compared them while bench testing with my MegaSquirt, and the difference was shocking.
The 2nd gen ignitor can switch a much higher load before going into current limiting mode, and the spark duration is a lot longer than a J-109. It however needs a smart dwell device like an ECU to drive it. The J-109 is smart enough for this task I believe. If the transistor trick gives similar results to those I got when bench testing with my MegaSquirt, I may just stick with the transistor until I need a way to retard timing under boost, like when I get an SC.

evil_motors 03-31-05 03:17 PM

well i guess something isnt working on my car... im not sure if i just didnt hook something up right or if i am out of gas or what... but no start. i need to take the dizzy back out and put it in with the car at tdc. if that doesnt work i will need to find someone to crank it while i see if it has spark... but i am done for today.. if all else fails i will hook up regular direct fire or go back to points....

evil_motors 03-31-05 05:00 PM

so i figured out that i am a retard... so next nice day that i can get outside to play with stuff is when i will try again.. i had everything wired up wrong.. so now i have the negatives of the coils going to both places they need to.. and the ignition source is ready to be wired up to the positive sides of everything... i do have a question though.. on the second gen coil which one is positive and which is negative?

Jeff20B 03-31-05 05:03 PM

The 2nd gen coil has a small + and - at the studs on top. Remove the stock ring connectors, look carefully and you'll see them.

evil_motors 03-31-05 06:35 PM

okay so i guess i will take your advice and run one big wire for the ignition and thanks for the tip

White_FC 04-10-05 10:12 PM

Just to let you all know, you can use other ignitors aswell, not just the mazda j-109 style ones.
Bosch sell a huge range of different ignitors. Some are much cheaper than others.
I ended up using a bosch 249-9-222-067-016 (IIRC..) which cost $50australian brand new..

Go to a local bosch supplier and ask them to have a poke around in their books for you and see what ones will work. The one i've listed works fine with the stock first gen dissy and has integral dwell control. There are many others aswell, if your in america find one that is common to your local cars that have electronic dissy's

Oh and its far cheaper than new ignitors for a first gen :)

White_FC 04-10-05 11:40 PM

Edit: Derr... DP... My bad... :)

wecycle 10-02-05 02:24 PM

wasted spark
 
my 1979 SA will be getting a 1985 electronic distributor this week. (as soon as it gets here)
Next step seems to be a DFIS. Can I trigger an Accell ecoil with dual high voltage terminals with the j109 in the '85 distributor? If not could I run the leads from the reluctor pickup to a GM HEI module and use that to trigger the Accell coil?

MadDuck 01-18-06 08:20 AM

1 Attachment(s)
I did the mod on my FB last night. Result was great.

So I made this little diagram.

nick812 01-06-07 12:35 PM

Man after waiting to do this upgrade today i got the coil in but its different. the 2 fires going to th balst are tan. Link to pics. I am kinda lost now that I noticed the difference. So can someone help?

PLEASE!!!!!!!!!!

http://pg.photos.yahoo.com/ph/ncw812...?.dir=/bb91re2

nick812 01-06-07 12:56 PM

Ok after looking the color of the wires doesnt matter the top goes to the + of the stock coil and the bottom 1 goes to the - of the stock coil. Is this correct? It there a problem soldering wires or should i use connecters?

nick812 01-06-07 06:32 PM

Come on some one i was wanting to have this done today but got confused someone help.

nick812 01-07-07 02:27 PM

Really no one can answer my question? Another day waisted. I thought many people have done this. Its an easy question i am sure i am right but just wanna make sure before I hook it up.

Jeezus 01-07-07 02:35 PM

my guess is just hook up and try. trial and error my friend! I want to do this mod as well, but even the simple diagrams confuse me.

nick812 01-07-07 02:46 PM

Yea coil was different than the 1 in the pic. Can I damange anythng hooking it up wrong?

John64 01-07-07 06:24 PM

Well ask inittab, hes a friend and does not post on here anymore. He took it out after a few months and said this mod does nothing!

Kentetsu 01-08-07 06:06 AM

Color won't matter. Just wire it up according to the location of the wires and you'll be all set...

jfachner72 04-23-07 11:34 PM

Old thread I just found this and did it. I think its great. Not faster or anything but it does idle better and smoother and seems to start quicker too.

Jason

dj55b 04-24-07 09:31 AM

just adding this so that i can remember this thread so that I can forwaded to some newbs ...

StricklyOldskool 05-16-07 03:07 PM

I kinda read through this thread and was wondering if both Leading plugs fire at the same time with this setup. If this is how this setup workz... isn't that incorrect? Shouldn't one leading plug fire right before the other? The rotors dont hit the plugs at the same time (or do they?) From what I recall...the rotors dont sit on the eccentric shaft at the same angle. Using direct fire does seem like a better way to go...but this question kinda concerns me.

ccauley 05-17-07 09:33 AM

1st gen direct fire
 
I'm considering putting a 2nd gen crank angle sensor with a new michrotech ecu and ingition booster in my SE in order to go direct fire. Anybody try this yet?

ccauley 05-17-07 09:35 AM

I am considering bosh coils as well.

StricklyOldskool 05-27-07 01:34 AM

Can anyone answer the question I asked awhile back...still shady about this....

Jeff20B 05-27-07 01:37 AM

Hey I got a news flash for you. Guess what happens when both leading spark plugs fire at the same time.
































Kaboom!

kgray 05-27-07 01:42 AM

lol. did this last night and hardest part was mounting for sure. (Dont worry trochoid, no new holes were drilled and all stock wiring was unmolested, new connections are crimped and shrinkwrapped. you would be proud lol) oh did i mention acceleration? I know some think that there is little to no difference for the upgrade, but i truely think there was some extra down low...


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