luiml73

iTrader: (1)

While searching for spark plugs, I've seen a few people running direct fire on the leading plugs.

This is how my car was set up when i bought it. Its running 2 6AL's and 2 msd blasters but still using the dizzy on L and T.


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Would there be any benefit in changing to direct fire and run NGK's Leading bur7eq trailnig br8eq14?

Or should I just leave it as is, and run br8eq14 all around.

If i do decide to convert, what other parts am I missing?

Thanks

t_g_farrell

iTrader: (1)

Wow! I have to wonder how much those MSDs are really helping out. To do that and NOT do a
DFIS seems like a waste of resources. DFIS would definitely help some on the leading.

luiml73

iTrader: (1)

Lets see If I understand this correctly. The 2 msd's are taking the place of the igniters? So all I would need now, is to add another coil. 1 to the dizzy "T" and the other 2 coils go to the leading plugs? I would also need a pair of 2nd gen wires?

t_g_farrell

iTrader: (1)

Basically yes.

Jeff20B

iTrader: (13)

You don't need 2nd gen wires. Where will the two leading coild be mounted? If close enough to the engine, the current wires can be reused.

And you can leave trailing exactly as it is but move the wires to the leading part of the cap. It'll make sense once you get started.

luiml73

iTrader: (1)

Thanks for the help guys. So when I install the 3rd Accel coil, can I just jump power for it from one of the other coils?

Dave.Martin2008

yes to do the DFIS if I remeber reading it correctly and I am sure Jeff will correct me if I am wrong take the neg off rhe first leading coil and run it to the second positive terminal and then the neg. terminal off the second leading coil to ground I have been told they run better that way... something about waste spark and all. I run mine off 2 J-109 ignitors I beleave is what they are called and i run each coil direct from each ignitor. with having 2 MSD's might want to look into running each coil off one MSD but that might be a waste of MSD power also not sure...

black82gsl

iTrader: (3)

I would surely do the dfi. You have all the parts you need basically. Go buy another coil, you can get one right at autozone. While at autozone they sell individual "universal" plug wires. Buy 2 of them for like 10$ and you're good to go. Or if you want to spend more money just buy some accel or other brand of wire sets they have on the shelf and cut your own plug wires. I bought the universal v8 kit because that's all they had. So I have a bunch of wires,ends,and boots left.
Here's the page I used to lead the way of the dfi conversion. It's actually very simple to wire.
http://www.smbaker.com/sand-rail/mazda-rotary-conversion/msd-6a-direct-fire-ignition-for-mazda-rx-7-rotary-engine


I posted a question about this but had no reply. My coils jump positive to positive and negative to negative. I assumed that was correct from what I've read. Is there any benefit from wiring them the other way?

TheRX7Project

iTrader: (3)

FWIW I've read that running 2 coils off a single MSD does cut the power to them slightly, however I've been doing it that way for 3 years and have not had any issues.

Dave.Martin2008

as far as I have read you get a better charge running them in series instead of parallel. I have mine pos to pos and neg to neg right now also. This is something I have come across recently.

t_g_farrell

iTrader: (1)

Just think of an MSD as a fancy ignitor. Using a single one will be less effective than
using one per coil for the leading. How much less? May be negligible.

black82gsl

iTrader: (3)

So msd orange to first coil positive,msd black to first coil negative. Jumper wire from first coil negative to second coils positive and second coil negative to ground. I will have to try this out when I get home. Make sense there would be more power ran in series. If it works like batteries in series it should technically double the voltage right?

Dave.Martin2008

No orange to pos first coil neg to neg on second coil. From MSD then jumper wire from first coil neg to pos on second coil.
The way you typed it you would not power the second coil at all. But you also had it right in thought of batteries. Not sure that it doubles but you end up using what piston engines call waste spark.

black82gsl

iTrader: (3)

Oh ok. Duh. I don't know what I was thinking. Same way I had to wire my trolling motor on my boat. So does this make a difference over parallel?

Sorry don't mean to hi jack a thread here!

Cookboy

iTrader: (10)

I called MSD to ask about that. Was told that it would not cause undue wear/harm to the msd box, but that each coil would get only 1/2 the voltage. I run MSD into a 2nd gen coil for mine.

dbragg

iTrader: (7)

Me too.

TheRX7Project

iTrader: (3)

I'm running mine parallel, pos to pos, neg to neg as if they are one coil off the MSD. Seems to be fine.

black82gsl

iTrader: (3)

That's how I had mine. Now I have it in series. Don't know if it really made a differance or not?

luiml73

iTrader: (1)

Here's a question for you guys. What do I need to do, to eliminate the 6al's all together? They make a lot of noise in the cabin and take up too much space. Plus, it looks horrible.

Switch to a newer distributor with igniters?

t_g_farrell

iTrader: (1)

Go HEI instead. See the TFIDFIS link in my sig.

luiml73

iTrader: (1)

So I eliminate the both the yellow Accels and msds with this setup, but still need a FB distributor?

Cookboy

iTrader: (10)

The hei ignitors replace the msd boxes.
See the thread mentioned above.

luiml73

iTrader: (1)

My question really is, can I still use my Yellow Accel Coils? Or do I need to replace them with Ford coils you guys are using?

Cookboy

iTrader: (10)

The accels will be fine. T. Farrell used the TFI's because he was in a junkyard and they suited his whim, near as I can figure. You can use his thread to wire the HEI ignitors to your coils and it should work just as well.
The debate over which coil is best is an exercise I choose not to pursue. I'd rather drive.

luiml73

iTrader: (1)

Is the only reason for using the HEI over the J109's is price and availability? My buddy says he has around 50 of those109's in his shed.