HAILERS

Is there any merit in mounting a second LEAD coil assy next to the one that is in place, splicing off from the existing 12 volt and 5 volt on the original plug to the extra Lead coil assy, and having one coil assy dedicated to each LEAD plug? Outside of the extra two lbs in weight, are there any merits or demerits for running like this?????

prmazdarx7

bumping th threat i am kind of curiuos now tha u mention it

so someone please enlighten out brain

riffraff

that is going towards a direct fire system.. more and stronger spark to each plug..

hypntyz7

Try it and see! Thats the kind of thing that might or might not yeild gains, but youd think if it would the factory would have put biger coils there to begin with.

MasteRX

I was wondering about something kind of similar. Like if you had an ignition box, could you get it to fire two individual coils at the same time by wiring two coils in series? Would there be to much of a current loss by wiring this way? Or would there be too much resistance for the CID box by running the two coils? If not, then it seems to me that this would be beneficial over using the stock primary coil. They say that the stock coil is supposed to be pretty good, but I have a hard time believing that it is better than a pair of quality high-perfomance aftermarket coils.

Samps

Irv runs a separate ignition box on the leading and trailing; he would probably have some good input on this. HAILERS; are you suggesting using two aftermarket ignitions? or two stock leading coils? I would think the added spark of an extra stock coil would probably equal the spark generated by an aftermarket ignition box running on the leadings. I'm thinking that if you happened to already have a spare leading coil that you could save a few bucks and just run the two stock leading coils and no aftermarket box. Maybe I'm missing the whole point.

HAILERS

I'm using two factory stock LEADING coil assy. Just spliced the two wires that go to the original coil assy to the spare one that I have. The car runs just fine. But I ask myself, if there was any merit to doing so, someone would have mentioned it a long time ago. I have not decided if I can tell any difference. I've redline it in 1st thru fourth to 7800 rpm and feel no ill effects. But then again I can't say it feels better either. The stock configuration never gave me any heartburn either. I've done this on the N/A, not the turbo.But then again, I'm not very sensitive about this type thing. We're talking subtle nuances here. Probably need to drive it on a long trip.

Samps

Maybe better gas milage? What happens if one goes bad while the car is running? I run a HI-6 and can honestly say it revs smoother. In other words, I noticed a difference when adding the ingnition box. If you noticed no change maybe there wasn't one. But even if you could get 1 extra mile per gallon, with the price of gas right now I would stick with it.

Keith

Two quick comments here. If you wire 2 coils across a single CDI unit, they must be wired in parallel to get full voltage across both coils, so you get sufficient secondary voltage. Of course, there will be a loss of amperage. To get max. amperage with this setup and not fry a CDI, use a Crane HI-6 or an MSD7 (an MSD 6A will fry). Also, use Universal coils, not CD-only coils, as these will fry almost any CDI due to their extremely low primary resistance.

The only advantage to firing each plug with it's own coil with the standard setup is you eliminate the power loss necessary to fire the waste spark across the other plug. Is this power loss significant? I honestly don't know, but I eliminated it anyway. I am not able to compare the difference between these 2 setups, since no company makes a CD-only DIS high-performance coil replacement. Accel does make a DIS high-performance coil replacement, but it is designed for a standard ignition upgrade, not a CDI upgrade, so I don't know if a comparison would be valid. I may try it one day.

Irv, Keith's dad

RETed

You talking about a dual-tower coil?
MSD makes a single-tower DIS coil specifically for their DIS boxes.


-Ted

Keith

Hey Ted,

Yes, I am talking about a dual-tower coil. MSD's single tower DIS coil does seem to be CDI only, but could not be used in our leading plug setup. The reason for this is that a DIS box cannot fire both sides simultaneously - only sequentially. Common power supply design causes this. So, if you had a DIS-4 box feeding 2 DIS coils, that works fine because the coils fire sequentially - one coil every 180 degrees of crankshaft rotation. If you were to replace the stock coils with 4 MSD coils, you would need a second DIS-4 box to fire the second coil in each set, unless you connected them in parallel to each DIS side - not likely, these are CDI-only coils and would fry the MSD, since it is the same capacity as a 6A. So, we come full circle to my setup - 2 MSD-6A boxes each firing its own MSD coil, both commonly triggered by the leading ignitor. (I used Crane Fireball ignition parts, but it's exactly the same setup.) That's why I mentioned the universal coils in parallel setup above, or the Accel DIS hi-performance replacement coil (it could be fired by a single box just like the stock coil) for comparison. Food for thought, isn't it?

Irv, Keith's dad

RETed

You can wire in a DIS-2 into a pair of those DIS coils, and flip the switch for wastespark.&nbsp This is a VERY EXPENSIVE option!



-Ted

Keith

Ted,

Veerrry Interesting! Do you know if this is a parallel or series hookup? Is the switch on the DIS-2? This is a new design that I am not familiar with, any information would be appreciated! Thanks!

Irv, Keith's dad

RETed

It's basically a parallel coil system.&nbsp The DIS-2's are a little over $300 each!&nbsp Some FD guys use a DIS-2 (in "normal" mode) to fire trailing coils.&nbsp Those MSD DIS coils are like $40 each, so you're talking about a $400 set-up just for leadings!&nbsp Wanna do the trailings?&nbsp That's another $400!

Yes, the DIS boxes have a DIP switch setting which will let them run in "normal" model or "wastespark" mode.&nbsp In normal mode, it'll fire each channel indepedently as triggered by it's appropriate input trigger.&nbsp If you switch it to wastespark mode, the DIS-2 will trigger BOTH ingition outputs whether the input #1 or input #2 was triggered - this is what you're looking for.



-Ted

Keith

Thank you Ted. I would love to get a scope on the discharge signal to see if it is the same as normal mode. Maybe if I win the lottery...

Irv, Keith's dad

slvr7

iTrader: (1)

When I installed the MSD 6A on my leading ingition, I also replaced the factory coil with two MSD 'Blaster' units. One per rotor. They are both charged by the MSD and fire simultaneously (waste spark arrangement) just like the factory coil would. I talked to the MSD techs about this and they said the CDI box would have "no trouble charging two coils, it could probably charge half a dozen".
Can't say whether it matters or not ( replacing stock coil). I figured it wouldn't hurt, it was the recommended set-up on the Paul Yaw website. Overall the change to the MSD & coils made the throttle response a little crisper, and smoother at idle. But measurable power? I dunno.

slvr7

iTrader: (1)

When I installed the MSD 6A on my leading ingition, I also replaced the factory coil with two MSD 'Blaster' units. One per rotor. They are both charged by the MSD and fire simultaneously (waste spark arrangement) just like the factory coil would. I talked to the MSD techs about this and they said the CDI box would have "no trouble charging two coils, it could probably charge half a dozen".
Can't say whether it matters or not ( replacing stock coil). I figured it wouldn't hurt, it was the recommended set-up on the Paul Yaw website. Overall the change to the MSD & coils made the throttle response a little crisper, and smoother at idle. But measurable power? I dunno.

RETed

Yes, we heard you the first time...


-Ted

Samps

Still no one has mentioned what would happen if one of the coils failed. Would that not mess up the whole system. What happens when one rotor is spinning at full stream and the other is crapping out?

RETed

Trailings will merrily fire the rotary engine.&nbsp It's the same with just the leadings only.&nbsp If one fails, I doubt you would even feel it.&nbsp Don't believe me?&nbsp Unplug either the leadings or trailings and go drive around...


-Ted

Samps

Interesting! We spend hundreds of dollars trying to increase our leading spark; but the system will still function without it.