Plug gap
- Thread starter nodemon
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Nope.
By increasing the plug gap, you’re demanding more of the ignition system. If the ignition doesn’t have high output, like a stock ignition, don’t widen the gap.
junkyardhero
Well-Known Member
Whatever. lol
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
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Just so you know and not to start an argument. ........
From 1999 to 2023, I had the very same copper plugs in my car. The only reason I replaced them, was cuz I thought/was pretty sure, that the car was sold, and I promised the buyer I'd tune it up.
Those plugs;
> probably had well over 100,000 miles on them.
> had seen three cams, three intakes, four or more carbs, 4 different 4-speeds, and just about every rear gear ratio in the Mopar line up;
> and they were still going to 7200,
> and still firing right up, hot or cold, and every where in between.
I'd tell you my secret, but sureaschit, somebody will tell me how wrong I am; and I'm just so tired of the party-line around here.
Here are some things I can tell you;
1) I don't have a Multi-Strike. and
2) I got my recipe from a Book authored by Smokey Yunich; and Yeah, that's a name drop, but try finding a better one around here.
3) for fuel economy, a wide gap helps, as long as your system has a good HO-coil. and
4) I have a recipe for going over 30mpg, with a 360, using 340 sized cam, headers, a 4bbl, overdrive, and
with a wide plug gap btw,
but every time I tell it, I get called a liar. But see, the thing is, I've already done it, long before I ever even heard of FABO.
So I know it is possible.
HOWEVER,
without a plug gapping tool, you cannot properly gap a standard plug to 080. If you are diligent, you can get to about .040/045, and then the strap will no longer be parallel to the tip of the electrode. If you install it like this, the strap will just spark from the closest point to the tip, which may still be closer to .035....... but good luck getting them all to the same funky gap.
So, if you want to try a wider than 035 gap, either get the gapping tool, or buy pre-widegapped plugs.
BTW
IMO
Forget running an E-core coil on a non CDI ignition system. Oh sure it works, but the turns ratio is all wrong for a regular style Electronic Ignition system. You may get lots of voltage but a weaker amperage. Just get the big yellow Accel Super coil, with it's matching ballast. It's a one-time super investment. Not cheap, but mine has never in 25years let me down.
OOps, my secret is out..........
From 1999 to 2023, I had the very same copper plugs in my car. The only reason I replaced them, was cuz I thought/was pretty sure, that the car was sold, and I promised the buyer I'd tune it up.
Those plugs;
> probably had well over 100,000 miles on them.
> had seen three cams, three intakes, four or more carbs, 4 different 4-speeds, and just about every rear gear ratio in the Mopar line up;
> and they were still going to 7200,
> and still firing right up, hot or cold, and every where in between.
I'd tell you my secret, but sureaschit, somebody will tell me how wrong I am; and I'm just so tired of the party-line around here.
Here are some things I can tell you;
1) I don't have a Multi-Strike. and
2) I got my recipe from a Book authored by Smokey Yunich; and Yeah, that's a name drop, but try finding a better one around here.
3) for fuel economy, a wide gap helps, as long as your system has a good HO-coil. and
4) I have a recipe for going over 30mpg, with a 360, using 340 sized cam, headers, a 4bbl, overdrive, and
with a wide plug gap btw,
but every time I tell it, I get called a liar. But see, the thing is, I've already done it, long before I ever even heard of FABO.
So I know it is possible.
HOWEVER,
without a plug gapping tool, you cannot properly gap a standard plug to 080. If you are diligent, you can get to about .040/045, and then the strap will no longer be parallel to the tip of the electrode. If you install it like this, the strap will just spark from the closest point to the tip, which may still be closer to .035....... but good luck getting them all to the same funky gap.
So, if you want to try a wider than 035 gap, either get the gapping tool, or buy pre-widegapped plugs.
BTW
IMO
Forget running an E-core coil on a non CDI ignition system. Oh sure it works, but the turns ratio is all wrong for a regular style Electronic Ignition system. You may get lots of voltage but a weaker amperage. Just get the big yellow Accel Super coil, with it's matching ballast. It's a one-time super investment. Not cheap, but mine has never in 25years let me down.
OOps, my secret is out..........
Looks like your timer was right on the money.
junkyardhero
Well-Known Member
like a broken clock, i'm right at least twice a day.
cue the HEI whisperers. those .060 plug gap wind talkers, worshipers of mpg and power, their language is sacred.
hark! they bellow down: ye of little faith know not of the ancient tomes! for we done did that **** before this here interwebz! behold and be amazed by what we accomplished in the past and mind not the present! this is our knowledge, so has it been written, so shall it be!
junkyardhero
Well-Known Member
that's some race car ****.
Translation: It's all boosheet.
Yeah. Side gapping does nothing unless you're running some of the hottest ignition you can find and then it doesn't last long. But 24 year old spark plugs.......and Radial T/As. Yeah. muh huh.
junkyardhero
Well-Known Member
careful, i think they keep detailed notes on the blasphemers.
for like, when judgement time comes or whatever.
Unfortunately, when people think of bigger plug gap benefits, they only think of peak hp. Not that it might give you a smoother idle or more miles per gallon. A smoother idle would mean the misfire is not as bad....& the hp went up. When GM developed HEI with up to 0.080" plug gaps, it wasn't because they had cash left over from the year before.....to splash.
There seems to be some diminishing returns with widening plug gaps. Peak HP is one thing, but again when an engine is at peak power/load/torque you’re going to be around peak demand for your ignition.
If your ignition can’t supply the output, it can’t keep supplying the needed spark at peak. A bit like the duty cycle of a welder. Spark may be good at idle, but run out of steam at peak demand.
If your ignition can’t supply the output, it can’t keep supplying the needed spark at peak. A bit like the duty cycle of a welder. Spark may be good at idle, but run out of steam at peak demand.
Yeah, at which point you’re probably better off running surface discharge plugs anyway. Which is what the ‘side gapping’ is basically emulating.
It's not diminishing returns. It's abuse on the ignition system. Wider plug gaps increase resistance and that builds heat in coils and ignition boxes. There's no need for anything over a .045" gap. Ever. You buy into the crap if you want to, but it's just that. Crap.
All of that nonsense is snake oil.
No I don’t buy into it at all. All it does is increase demand on the ignition. Unnecessarily.
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
- Joined
- Jan 19, 2014
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As per the usual, some guys here are like Christians, you can't teach them anything, and nobody knows better than they do. Like Pharisees they preach out of the sides of their mouths, and worship othergods.
>Up here in Manitoba, the cheapest gas, 87E10, now costs close to 1.60 per liter; which is about $112 per 70L tank/which is about 19.25 USgallons..To me that is about a full days wages at minimum wage. To a retired and married guy like me, that's like two and a half days worth of groceries. IDK how that works out in America.
> When I was a kid pumping gas, I remember I could buy about 4gallons C/18 liters of gas for an hours labor at minimum wage. Today, those 18 liters cost me over 26 bucks, almost double of minimum wage. but if you compare that directly, gas now costs over 22 times as much...... and gas is never gonna get cheaper.
> So, if you're a Canadian-streeter, IMO, fuel mileage should always be on your mind.
To whit;
If yur gonna buy an ignition system anyway,
you might as well buy one that is gonna, at cruise rpm,
help burn ALL the fuel that is going into the engine, and
get as much torque out of that fuel as is possible,
running it as lean as you dare.
But honestly; Synchronizing Power with Economy, starts on the drawing board.
IMO;
Once your open-chambered, low compression, maybe dished-piston, 340-cammed, 125psi-dream-engine, is on the motor-mounts, yur screwed anyway, no matter what the plug gaps look like.
Well;
I run my Accell from a relay, direct to the battery, triggered by the ignition switch, so, I don't pull those amps thru the bulkhead connector. My coil pulls about 9volts/hot on the run circuit. And yes, like I said, the coil is still going at 25 yrs old ....... so, that's something you can do.
But the really big deal, for hi-way economy, is keeping the rpm down, the cylinder pressure up, and with adequate Ignition timing.
8/1 @2800, with 28*timing, is not gonna cut it. You can justabout watch the gas-gauge drop while you're driving.
My current recipe is;
over 11/1Scr/ 185psi/ cruising at 2240 @ more than 50* of cruise-timing, with more available/ OOTB Edelbrocks installed over KB107 flat-tops @.032 squish, with a wide top gap. Until fall of 2023; the Copper-plugs were screwed in, back in 1999, with the gaps just eyeballed.
For hiway economy at 65=2240 ...... or less,
>the best carb to use is a small-primary, spread-bore, metering-rod-type,
>on a matching Dualplane, running fresh cold-air, and as already stated, 87E10.
>I normally run a 750DP, but for long-distance, I have a prepped carb. I mean it takes less than 5 minutes to swap them.
> I have not played with plug types or gaps. I just depend on that Accell coil to deliver.
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junkyardhero
Well-Known Member
i believe the word you're looking for is philistines.
i am, after all, just three raccoons in a trench coat.
Standard point ignition, gap them at .035 as designed. As they wear they will be at .040 or so when it's time for a new set. The spark lights the fire. No reason to reinvent the wheel here. If it's not going to make a big power or mileage difference, why even bother. Gap them, screw them in, and drive away.
but, but, but.......there's E3s. There's Splitfires. There's HEI conversions. There's .080" plug gaps. All that's just gotta be better. lol
junkyardhero
Well-Known Member
did you not see the article posted above!??
average 5hp!! that's a SOLID 0.048% increase!! and that hasta be worth at least another 558ft per gallon!
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