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-   -   (ELECTRICAL) EASY 2nd gen direct fire install - 20 minutes (https://www.rx7club.com/1st-gen-archive-71/electrical-easy-2nd-gen-direct-fire-install-20-minutes-398818/)

Slammed_GSL 09-12-04 06:20 PM

Sorry for being such a dufus but I need you to explain what you mean by inline?
-negative to negative, a loop from the -neg FC coil post through the ballast resistor and back to the -neg FC coil post?

Jeff20B 09-12-04 11:07 PM

1 Attachment(s)
I looked more closely at my coil and saw that the + side has the ballast resistor. To hook it up to a J-109, I'd probably do something like this.
https://www.rx7club.com/forum/attach...chmentid=73530
I'd leave the ballast resistor in its home of course. The exploded view is merely for illustration purposes.

Slammed_GSL 09-12-04 11:21 PM

Thanks Jeff, that was the missing part of the puzzle, Chris I think had his inline with the -negative if I read his install correctly, my coil had the ballast inline with the +positive side(yellow wire instead of the black Chris had). I will give this a try and report back.
Thanks again for the drawing(they help so much when it comes to wiring)

Jeff20B 09-12-04 11:58 PM

Thanks for the positive feedback! I tried to make the basic components recognizable. I even included the Mitsubishi three diamond thingie. :) I'm sure that little ignitor image will come in handy many more times, as will the 2nd gen leading coil, to a lesser extent. I could actually update my DLIDFIS diagram with the ignitor image if I wanted to. :D

Go ahead and try the ballast resistor on each coil terminal and let us know if one way has any more power than the other. Logically, it probably won't make a difference, but at this point, you might as well give it a try. Thanks!

Slammed_GSL 09-13-04 11:53 PM

Ok, I got the Ballast resistor connected on the -negative side, between the FC coil and the Ignitor. I noticed that the idle was better and it seemed to run quite well. The butt dyno thinks I gained some grunt and pull when I mash it down to the floor, no hesitating...still back fires....that's just my style of driving I think.
Thanks again to Chris for the idea and Jeff for the follow up tech drawings!

Jeff20B 09-14-04 02:55 PM

Awesome! Another late leading igniton system runs!!

By the way, I use late leading as a blanket term to describe any leading ignition system that fires the leading plug once at TDC/0º and then again 180º later. It can be used to describe any number of rotors (such as for my 20B or my planned single rotor project). This gets me away from all the self-limiting acronyms such as DLIDFIS, TLIDFIS, 2GCDFIS, SRLDFIS, SLIDFIS, MSD-DFIS, well, you get the idea. :)

It's a term I borrowed from the R26B's late trailing ignition system where it fires all threeplugs per rotor face at the same time. The third spark plug, located above the normal trailing plug, fires into the trailing edge of the rotor face as it is compressing the incoming air fuel mixture. Late leading, on the other hand, fires into the trailing edge of the rotor face as it's expanding right before the exhaust port opens (it can fire quite a bit before the exhaust port opens if advance is set high enough).

As for how the obvious differences differ from each other, and what it all means in the end, I'm not fully sure at this time. All I know right now is taking advantage of the leading plug's larger hole to put spark into the trailing edge of the rotor face seems like a somewhat better idea than having a tiny, extra hole in the compression area of the rotor housing. Mazda found that this extra hole allowed enough blowby to no give an increase in HP. So even with the extra spark, it only improved gas mileage a bit. Of course for a long race such as Le Mans, fuel mileage is very important. If you have any questions about the R26B's late leading stuff, be sure to ask Evil Aviator.

gonzz 09-14-04 09:04 PM

I was checking my timing today and the timing light didn't work on the 2nd gen coil wires. Do I have to do something special? I got a 80 ignition setup...

Jeff20B 09-14-04 09:38 PM

Hook it to your trailing coil output.

Make sure to hook it to the coil to cap wire and see if your timing light continues to not work. There may be a problem with your timing light's timing circuitry which causes it to not flash with double the amount of sparks going to it.

My old timing light died so I've got a friend's here. His timing circuits are painfully slow and it skips several sparks in a row. It makes me think I have a misfire even though I don't. I need a new timing light.

gonzz 09-14-04 10:16 PM

It works on the trailing just not leading

stobrien 09-15-04 06:51 AM

trailing
 
I installed 2nd gen direct fire on the weekend. Today I was setting my timing, I had no problem setting the leading, but when I went to adjust the trailing it did not matter how much I adjusted it there was no change.
Any Ideas
85 GSL-SE

Jeff20B 09-15-04 02:19 PM

gonzz, you'll need to confirm the leading coil works in some other way. Try pulling a spark plug wire off the coil and hold it near one of the strut studs. Then crank the engine and see if a spark jumps.

stobrien, remove the cap, rotor and metal cover. Locate the trailing pickup by either following the wires from the back of the trailing ignitor, or by following the little connecting piece of metal from the trailing vacuum diaphram over to the pickup. Next, loosen both screws and then push and pull on the diaphram canister thing and confirm that the pickup rotates slightly by a few degrees either direction. If it does, you're good. If it doesn't, you'll need to work it free because the grease may have hardened over the years.

Are you trying to set trailing for a 10º split? I don't have access to a GSL-SE anymore, but if I did, I'd at least try it. All my older carbed 4 port 13Bs have a 10º split. It seems to work ok. Infact, two of them actually have GSL-SE dizzies to take advantage of the slightly higher total mechanical advance they can provide.

I can't think of anything else off the top of my head.


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