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Just don't mix. I was about ready to throw my cams out for the constant idle misfire and CE light that wouldn't quit. So today I tried a set of new NGK plugs, gapped to .060". Wow, what a difference. It idles almost as smooth as stock now, and the low speed "light switch" power is smoothed out some too. Amazing what a good spark can do. BTW, my old Champions only had 14600 miles on them, and looked almost new.
 

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I'm sorry for sounding dumb but how are you able to get away with a gap of .060? Different ignition system? The spark off a .060 gap with the right coils and ignition would be huge!
 

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The stock ignition system is capable of producing over 100,000 volts. It takes less than 20,000 to jump a 0.060 gap under the worst conditions. The need for an upgraded ignition system for a stock engine is a myth perpetrated by manufacturers of ignition systems. [cough] MSD [cough]
 

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Why do they have the stock gap at .039 - .041? Plug life? At my next plug change I may have to gap them that large and see how it feels.


I run a MSD coil on my old 85 F-150 and the difference between the stock coil and the MSD coil was like night and day. So I would take it as the Subaru ignition system and coil pack are top quality or better engineered?
 

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Basically, the small gap makes a plug last longer, yes. The larger the gap, the more voltage that is required to spark across it. Higher voltage means faster plug wear. 0.040 is a good comprimise between "runs good" and "last long" As far as your 85 Ford is concerned, it's like comparing apples to oranges. The Subaru ignition system is not all that much better, but the overall efficiency of the engine is. A really efficient combustion chamber design with good fuel management really negates the need for a super hot spark or multiple spark ignition systems. Also keep in mind that as a coil ages, it weakens, especially the older oil-filled coil like on your Ford. How old was the old coil? It's quite possible that you would have noticed similar gains from a new stock coil.

Keep in mind that no matter how much voltage a coil is advertised to produce (some MSD coils claim to be 150,000 volts) the actual firing voltage is only the amount required to make a spark. In other words, if the spark plug only requires 15,000 volts to spark, that's all the coil will produce, regardless of what it is capable of. The spark voltage that is required varies widely during normal driving, anywhere from 7k to 25k volts.
 
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Stock cam and Champion plugs don't mix - don't know how you could stand it for 14k miles. :eek:

I swapped mine out after 7k I think.

And how is it that people say their oil looks brand new after 3000 miles? Mine is always black.

So how do your plugs look new? Mine are always dirty.
 

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horatio102 said:


So how do your plugs look new? Mine are always dirty.
Probably because I never short trip my car. If I know it's not going to get a chance to fully warm up, and by that I mean getting the oil to 180 (about 15 miles) I don't drive it, I take my truck instead.
 

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Most imports just don't need ignition upgrades (other than some NGKs). One of the more major VW tuners runs stock ignition on their ALCOHOL powered car. Old GM ignitions are notorious for crapping out at about 5k rpm.
 

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So today I finally got off my lazy ass and did the Single Point Ground mod, ran wires to ground points at both front inner frame rails, left front strut tower, sensor ground by coil, engine block near knock sensor, and front lighting ground by ABS unit. The verdict? just as I suspected, it made very little if any difference. Then again, my car has never really suffered from a hesitation that most people seem to get. It does seem to idle a touch smoother, but maybe that's my imagination wanting the car to be better since it worked on it!
 

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yes I used red wire, I had a 100ft roll.
 

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this would be much easier if I put all these pics on an image hosting service.
 

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yamarocket630 said:

Probably because I never short trip my car. If I know it's not going to get a chance to fully warm up, and by that I mean getting the oil to 180 (about 15 miles) I don't drive it, I take my truck instead.
Oh. Well. heh heh heh.. that might have something to do with it.

3 miles to class. 3 miles home. twice a day, two days a week, and another ~3 mile trip once a week. Then any driving around town.

I didn't really like driving the truck because the antennas hit the garage roof and it was a bear parking in the itty parking spots.

Oh well.
 
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And I was ready to put money on that ground wire thingy saying that it wouldn't do much. :)

But if it's rumored to cure hesitation, I might try it myself. I'll let you know.
 

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Hozay said:
I thought people were using 10-12 gauge wire. That stuff looks awful wimpy.
That is 12 gauge wire, bad pics.
 

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Well I just did it.......Took the car for a spin. What do I get......A big smile Definently took the hesitation away. The car idles smoother and revs smoother. Best 2 dollards Ive ever spent on my car. For the nay sayers do it. It's easy and quick and well worth it. What I did was use 10 gauge wire:


Ran one from the negative to the chassis ground right in front of the battery scraped the paint away.

Ran one from the ground on the motor (follow the 8 gauge negative to the block) to the driver side strut grounds. Scraped the paint on both of those

I then ran one from the negative on the battery to the other driver side strut ground.
 
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