2jzfc

86 NA, street port 6-port downgraded to a Weber 48 DCOE I'm trying to figure out how to get my ignition system wired up. Through all my research I think I have a solution, but want to run it by those who know and see if I'm doing anything wrong or missing a step or part.

Parts acquired:
MSD 6AL
x3 MSD Blaster 2 coils
85 13b distributor

Trailing plugs first, wire up single MSD Blaster 2 with ignition source power and chassis ground. Then run cable from the Blaster 2 to the center plug on the distributor cap which would be the trailing coil source. Then use the two trailing side plugs on the distributor, and run cables to my two trailing spark plugs. That should take care of the trailing side, right?

Leading plugs both fire at the same time and produce a hotter spark since they take care of the majority of the ignition in the combustion chamber. So cut the red and green wires from the "leading" magnetic trigger on the front igniter of the distributor, then wire the green wire from the trigger to the purple wire of the MSD 6AL. Then wire the red wire from the trigger to the green wire of the MSD 6AL. This should take care of the timing of the spark for the leading plugs, right?

Then wire the ground, power, and ignition source of the MSD 6AL. Then I need to wire the orange and black wires from the MSD 6AL to the last two remaining MSD Blaster 2 coils. Once again since leading fire at the same time, I can use one MSD 6AL to power both MSD Blaster 2 coils by bridging the orange power wire to the positive posts of the Blaster 2's and the black wire to both negative posts of the Blaster 2's. Then I should be able to plug in my spark plug wires from the Blaster 2 coils to my leading spark plugs, right?

Am I missing anything here? This is essentially a wasted spark setup right? ANY input, info, and correction please respond. This is the step I'm pretty much at with my FC besides all the body work being done atm. Thanks.

2jzfc

I know converting to carb and distributor is a big no go on this forum, super taboo. But a friend of mine found this article for me and it pretty much describes exactly what I'm wanting to do. So here it is for people looking down the road. Hope they find this.

MSD 6A direct fire Ignition for Mazda RX-7 Rotary Engine - Dr. Scott M. Baker

PinkRacer

We have a similar system on our N/A w/ a Weber 51IDA. I'm running 2 6AL boxes though, and not running it true direct fire, because we couldn't get it to run right on that.

I have 2 modded ignitors.

That article is a great reference - I used it many times!

2jzfc

So are you running 2 6AL's one for each coil for leading? What issues were you having? Anything else you did differently from the write-up?

PinkRacer

For some reason, we couldn't get direct fire to work properly, so we're running 1 6AL for Leading and 1 6AL for trailing, one Blaster 2 coil for leading, one for trailing, then back through the distributor. The modded ignitors sends signal to boxes, boxes send nice clean signal (with rev limits!) to coils, coils to distributor, distributor to plug. We're going to try wiring up the direct fire again at some point, but haven't gotten around to it.

2jzfc

Ok so you are just using another MSD 6AL to send stronger power to the trailing coil instead of just using an ignition power source from the car itself to the trailing coil. Kind of weird though, I've heard of people not running trailing plugs in their cars with little not no difference in performance. Granted they were EFI turbo cars and not carbed NA cars, but the spark from the trailing plugs is so weak it's a wonder you would be having issues like that. Thanks for the info!

PinkRacer

Funny story - a connector didn't fully seat one time on one of the ignitors, and I ended up with a car that started and ran (badly) on only the trailings. hahah

2jzfc

Wow I can only imagine how horrible that was hahaha