Glad to hear yours is working well. Are you using brand new 7 pins or junkyard ones? Maybe I have a bad one.

I went ahead and bought 2, 4 pin HEIs and I'll try it out this week and see
how it does.

all junk yard parts. Picked up two 7 pin 2 5 pin and a coil from a nissan. Round one like the stockers. Ill get some pics. Gotta tidy it up really quick. The way i did mine i think is awsome.

Love to see any pics. What coils did you use?

I used the two stockers and one from a late 80s nissan pickup.

there they are. Still not cleaned up like i would of liked it to be but soon itll looke all nice.

BTW if anyone is debating on getting the Moto Droid, Thats what i used to take these pics with:)

I'm not sure that mounting your coils on your keg is a very good idea.

well idk, Ill find out if it is or not. So far so good

Vernuil, great pics its always cool to see how others have done these kinds of mods.
The coils on the keg should be fine, they can handle the heat. The only drawback I
can see is that the Nissan coil might not contain its oil on its side but time will tell.

they do. Theres were two on the truck i pulled it from. One on its side and the other vertical. So I think it shall be good to go. Ill get the bay cleaned up soon. From this mod, It really woke up my RX, Seems a tad bit more snappier and a good bit of more power. Smoother and higher rpms also. Wish i knew about this when i had my first RX, And i should of kept my 6aL, That probly woulda given her some extra pep. know to move on towards boosting:)

So I swapped in my new 4 pin HEI and it seemed to help some but
with the timing light I could still see something weird happening at
around 5 to 6K rpm. It would sit at max advance (~22 deg) at 4K and
then would sometimes look way advanced (the markings would disappear)
and I would hear it in the engine as, I guess, misfires. Anyway, I started
looking at my dizzy. I have an 80 SA dizzy, so I'm thinking the signal from
the reluctor wheel is getting messed up somehow by the time it gets the
HEIs.

Well I happened to have bought an FB dizzy from someone last week and
I was comparing, looking to see if I should swap this in to see how it works
when I noticed a huge difference in the reluctor wheels. The FB reluctor wheel
is much more aggressive and I think would result in a more defined and sharper
signal to the HEIs. I'm wondering if this is why, Verneuil, yours worked so well
compared to mine.

Not only are the profiles radically different but they look like they would
produce opposite looking wave forms as they pass the pickups. I'm going
to wire up the FB dizzy and drop it in next and see what happens. Since
I'm wiring it up from the dizzy I'll shorten the dizzy to HEI harness while
I'm at it. Right now it runs down the side of the engine, under my alternator
and over to the shock tower. The new one will go directlty over to the shock
tower ( with slack) to the HEI, which should cut the length almost in half,
plus I'll twist the leads to help stop noise.

Heres the 80 reluctor:

http://lh3.ggpht.com/_yHWw1b7rWdc/S8...rx780dizzy.JPG

and heres the 85 reluctor:

http://lh4.ggpht.com/_yHWw1b7rWdc/S8...rx785dizzy.JPG

Hmm ya that could be ur problem. I twisted the leads also. I used a drill soooo much faster. Ill probly end up getting some shielded wire from *work* Coast guards got soo good stuff. see if i can get some scraps.

Tim,

I know that the green and red wires on the SA dizzy need to be swapped compared to an FB dizzy (see how the teeth are basically flipped around on your two pics?). If you are having trouble with the SA dizzy, try switching the wires around from the dizzy to the HEI.

Kent

I second that. You will be continually heat soaking the coils. They may live there for years without problems but the heat will certainly negate the improvements. The FD and FE guys make brackets to move the coils off the motor.

-billy

I kinda disagree with that. Manufacter's have been mounting coils on top of the engines for many years.

Yeah I already had determine that and had the on the way that ran the best. Its
just at ~6K things would breakup, hesitate. I can tell from looking at the reluctor
wheels that they would likely be reversed. We'll see.

I'm not getting into this debate. I might have put my TFI coils on the keg
except my Dell air cleaner is in the way.

Ok, heres some interesting and good news. I ran out at lunch and swapped in the
FB dizzy. I think its the one Kent rebuilt for rx7guy666 whom I bought it off of last week.

Anyway, the hesitation appears to be gone. I had to swap the reluctor leads
connecting into the HEI because, indeed, the signal is reversed from the SA
dizzy signal. I'll be taking it for a test drive later today to get brewing supplies.
So I'll report back after that.

I think its safe to say the SA electronic dizzy was a weak link in this mod. The
combination of the HEI away from the dizzy, the old reluctor design and the
fact the the air gap on it was .0025, when .0024 is the upper limit all combined
to cause an erratic signal at higher RPMs. I would have loved to put an O scope
on those signals so I could see the waveforms.

So how weak of a link is the SA dizzy compared to the FB? Reason asking is because I have an SA.

Well atleast the 80's dizzy.

Glad to see it is running right finally, good spark is a great thing to have!

Just got back from a nice cruise down 77 to 485 to 74 and back. This ignition now
officially kicks butt.

All I have to say is "Wow!"

I'm at redline before I know it. My Dell stumble is almost gone. I really have to be
careful on 1st ro 2nd shifts or it breaks the wheels loose everytime.

Now I want to set it to the Yaw timing and tune my Dell a bit. Its been awhile and
I think the Dell needs some tweaking.

I think its a major weak link. Otherwise Mazda wouldn't have made the huge
changes they made in 81. More aggressive reluctor wheel, mounting ignitors on
the dizzy, messing with the mechanical advance curve. Get yourself an FB dizzy
as soon as you can. I can't say more.

Tim, or Stu, I have a couple of FB dizzys sitting in the garage. I know I have a good set of ignitors as well. Just so you know :D

I have extra j109s and j105s as well. Theres no mazda igniters in my car now :)

Thanks for the offer Sam.

..........And modifiers/racers have been moving them off the engines for years............

Also, any manufacturer mounting coils to the motor would try to isolate the transfered heat though a rubber or plastic spacer. There would still be radiant heat.



-billy