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Discussion Starter · #1 ·
Hi Alex,

Accel and MSD (probably others too) have or are coming out with higher-output coil packs for our cars.

I note that, at least for my 2013 ST, the coil pack is the same part number as my daughter's 2012 Focus SE.

Since we know a bigger gap means a higher voltage is required to make the spark, and that a higher-voltage spark is often beneficial, especially at higher rpms, with higher boost, higher octane fuels and WMI...

Where does Stratified stand please on running a bigger plug gap than you currently recommend when running a set of higher-output aftermarket coils?

Thanks!
Mark
 
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I wonder if these would help fix the misfire at idle that a good number of 2015 and 2016 models are having, me included.
 

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I was looking at these MSD coils as well - okay I admit it - I just think they look kinda cool. But I do have a BT/WMI setup with Stratified custom tune. Is there any benefit adding these and if so do I need something other than the .026 gap I currently have and would I need to re-tune?
 

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Discussion Starter · #7 ·
I was looking at these MSD coils as well - okay I admit it - I just think they look kinda cool. But I do have a BT/WMI setup with Stratified custom tune. Is there any benefit adding these and if so do I need something other than the .026 gap I currently have and would I need to re-tune?
What we found on my turbo rally car was that at high boost levels and smaller spark plug gaps, you could experience misfires because the spark (oversimplifying here...) essentially is blown out before combustion gets going appropriately.

Since the bigger the spark plug gap means you need a higher voltage to jump the gap, generating the higher voltage means you need a coil that can (at higher rpms) consistently deliver that higher voltage (which means more amps are drawn, coil runs hotter, etc. etc.)

But... if your coil can do that, then you don't get high rpm misfires (or at least this kind).

So the way I was thinking about this is as follows:

1. Our coil packs are the same as on many non-turbo models, so how much more juice can they be expected to deliver, especially on a tuned motor?
2. There must be a reason why all the tuners save Randy recommend smaller plug gaps. And certainly even on a stock car my own experience is that the car idles more smoothly with a smaller gapped plug.
3. So, if I can now buy a coil pack that has 10% -15% more energy than the stock coil packs, why not use that extra capacity to open up the plug gaps over what the tuners currently recommend, so as to get a higher-voltage, hotter spark and reduced risk of WOT high-rpm misfire?

That's all to it, really. Just asking Alex what his experience has been.

Mark
 

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Discussion Starter · #8 ·
I wonder if these would help fix the misfire at idle that a good number of 2015 and 2016 models are having, me included.

There is one way to find out for sure... ;-)

(I have a 2013, sorry!)

All the best,
Mark
 

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I wonder if these would help fix the misfire at idle that a good number of 2015 and 2016 models are having, me included.
I had the rough idle and with the AC on it was idiotically bad. It never threw an error but it was obviously missing cylinders. The fix was stupidly easy and I am kicking myself for doing it earlier (45k miles)

Spark plugs. When I took the ford plugs out they looked ok but were gapped 1.5 to 2 times what they should be. New plugs in and out for a test drive and I had to double check if the AC was on when idling.
 
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