Coil on Plug Conversion Questions

Advanced discussion of improving KA-T components
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Colorado S14
240sx Wannabe
Posts: 181
Joined: Thu Aug 26, 2004 3:21 pm
Location: Denver, CO

Coil on Plug Conversion Questions

Post by Colorado S14 »

I have a shiny new AEM Infinity ECU sitting here just begging to get wired in. I only want to build the wiring harness once if I can help it, and as such I think I would like to switch to a coil on plug system just to eliminate any spark issues down the road. The problem is that my car has been sitting for almost 5 years due to a lack of time/funds and amazingly over half a decade your brain gets a bit sluggish on all of the juicy knowledge you used to have.

There are a few helpful threads like this one (viewtopic.php?t=23985) that give some guidance, but I thought I would ask a couple questions here too.

I love the low profile nature of the CBR Coils and other coils like that (AEM Pencil, etc.). I know LS1 coils are tried and tested but the large non-coil on plug nature just ends up cluttering the engine bay and adding more complexity. I feel like I have heard somewhere that the CBR coils are not the most powerful options, what about the AEM coils or other alternatives that work in a coil on plug fashion?

What about CDI? I have never really run anything outside of a distributor with an external coil so this is all Greek to me at this point. The AEM Pencil Coil site says I need an external box or 4 channel coil driver. I would think the box gives me extra juice and better spark? Looking at ignition boxes, MSD had "CDI" boxes ranging from $150 for a Street Fire Ignition up to $700 for a High Output MSD-4, what do I need, what is overkill?

Thanks for any help, I like so many others, have done things the wrong way or the cheap way in the past with certain parts of my build and this time I only want to do it once and have it be reliable and quality.
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superDorifto
Dont Question My Nissan Knowledge
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Re: Coil on Plug Conversion Questions

Post by superDorifto »

The infinity just like the EMS 2/1 should be able to directly power any smart coil. That's a coil with a 5 volt trigger and internal exciters.

Maxima and VW Audi are the ones I've seen work with the KA Valve cover with minimal modifications. You should get actual dwell/voltage offset curves for whatever coil you plan on running.

The MSD boxes are known to fail and frankly just another thing that can go wrong. Look at my build thread or my posts in this section about running the VW/Audi Coils.
Colorado S14
240sx Wannabe
Posts: 181
Joined: Thu Aug 26, 2004 3:21 pm
Location: Denver, CO

Re: Coil on Plug Conversion Questions

Post by Colorado S14 »

Yea, looking at it now, I am thinking the M&W CDI is the way to go at the moment.
cmj
240sx Wannabe
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Re: Coil on Plug Conversion Questions

Post by cmj »

Colorado S14 wrote:Yea, looking at it now, I am thinking the M&W CDI is the way to go at the moment.
I really like that setup.. I just wish it was a couple hundred cheaper!
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street_240sx
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Posts: 1923
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Re: Coil on Plug Conversion Questions

Post by street_240sx »

I run ms2 with ls1 coils, turned my dizzy into a cam/crank sensor. As far as settings ive have to ask my buddy
03 evo8 gsr: stroker 2.3 ;)

04 evo8 gsr: totalled

96 integra gsr: sold

89 s13 coupe: stock dohc, gt3076, megasquirt

started 3/15/08, running 1/18/09, finally turbo 2/9/14 lmfao
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supakat
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Re: Coil on Plug Conversion Questions

Post by supakat »

LS2 D585 are the hottest coils but not a true COP setup. I personally have LS2 and rather function over form. The external box is an igniter like on stock ignition. It tells when to spark the coil. I would go with a smart coil vs dumb one just to eliminate the need for an external driver/wiring.
12.96 @ 116.36 - 2.1 60ft - 11/2011
13.1 @ 114 - 2.3 60ft - 8/2012
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