So, all of you are citing issues with larger gaps. What if you are running a .055 gap and having NO ISSUES. Fires right up. No issues with secondary components. runs great.....??

Could be related to compression I suppose, as I'm at a pump-gas friendly 10.5:1. ???

I'm willing to learn, but don't see how running a smaller gap could help me when I have no ignition issues to begin with.

(sorry to hi-jack, but I think we're on topic)

My only response would be you tried a smaler gap. The car may pick up. May even start better.
Mine would also always start at the larger gap just not as quickly and the plugs did not like it.

FWIW this post made me remember that the head whizz at Holley said in an interview that they are thinking about bringing back the MALLORY brand. I hope they do. Less money, more features and way easier to upgrade. But, if they just relabel MSD crap i'll be pissed.

If you can lightem, the wider the better.

Crizila, Can you enlighten us why it is better to have a wider gap? Why put more strain on the other ignitions components if there is no gain?

I'm not Crizila but the theory and reality of the wider plug gap makes the coil produce a higher voltage to jump the gap, more energy to jump the gap makes the spark hotter, correct? Same thing on spark plug wires that are resitor compared to non resitor wires, more resitance the more energy needed to get back to ground

Yes I realize that, but do you need a hotter spark, is a hotter spark going to give you a better performance. Back a while ago there was a tread on here and a number of top members stated (dyno testing)that they opened up the gap and they found that it did not give them better performance. As a matter of fact some said that a smaller gap produce a better result.

As stated, a wider gap puts more strain on all the other components. It will find weak spots.

The wider gap is a higher impedance for the arc to jump through. Yes, the arc is larger, but it is tougher to bridge the gap. The smaller gap is easier to jump and therefore can be a more reliable spark.

If the spark is adequate to produce a proper burn, no additional spark will have any effect............

The wider gaps came into vogue in the smog era, need a wider/longer spark kernel to ignite the lean mixture correct???

A better, bigger and better than you currently need,ignition and fuel system won't make you go faster if your current one fills the needs of the job
Sometimes, many times in some cases, a lot of racers don't realized that thier fuel and igntion systems are at the limits of what thier asking it to do until they see some other racer with a similar combination of car and parts and he is outrunning them on the same day at the same track Once they figure out what he/she, is doing different than they are and switch to that component and pickup thier car up to match the other car do they come to realize that they had a problem they didn't recognize or know about Many gremlins lurk in the shadows of racing parts and decisions

You wanna light that mix with a match or a torch? A larger, hotter spark WILL make more power, keep the plugs cleaner, less fouling, and do a better job of lighting a mix that isn't ideal ( smog era). Did I mention carbon bridging is all but non-existent with a wider plug gap. Why do you think top fuel cars run 2 plugs and ignition systems? More / hotter spark. A hotter spark will give you a more complete burn and more power every time. Of course, you can always play it safe and gapem at .030" - hey, got a match wennie boy?

I remember maybe the same thread. Around 07. Motor made most power at .28 gap. I had to change my plugs in my hemi ram and decided to gap them at .28 and i noticed increased fuel milage ( like 1.5 mpg) and i was SOLD

If you gapped your plugs that tight and made more power, you had other problems - namely a weak ignition somewhere - coil, wires, cap, rotor, wrong heat range plugs, etc. If the smog era did one good thing for us it was to produce a kick az ignition system. They ( the big 3)didn't have a choice in order to light that diluted, too lean, shatty mix they were dealing with. Multiple Spark Discharge, 8MM wires with better insulation, bigger caps with brass terminals, better coils and coil saturation time, all came out during the smog era. A Godsend for guys running "big squeeze" motors. If you have an ignition system that can put out 55K open voltage or more, no reason why you should be using it.

My pea-sized brain tends to agree with Crizila. I don't see how you could get better burn and make more power with less spark. The only way that scenario makes sense is that there are issues elsewhere in the ignition system, and when the gap is opened, the ignition struggles to jump the gap.

FWIW: Last year I did the Northwest Drag Tour, making several 4 hour highway drives in 100 degree heat. My MSD Digital 6+ box is mounted under the hood, and I run uncoated headers and said .055 gap in my plugs...... No issues whatsoever, in fact the car ran personal bests twice that weekend, and purred like a fat cat on the highway @ 3200 rpm for the entire trip.

As I stated above, it all has to do with the impedance (resistance) that the arc must jump in order to provide a spark. The more compression and the wider the gap the more difficult it is for the arc to start - google Paschen's law for details. If you are borderline on the capability of the arc starting across the gap the less reliable your spark will be. Closing the gap will improve spark reliability.

The larger the gap the higher the voltage needs to be before the arc starts. This stresses all your other components like the spark plug wires and you will be changing them more often and the spark will find the weak point so it may leak to ground through the spark plug wires before it arcs across the plug. Hence better reliability with smaller gap.

Also read my post above where with the hotter spark it kept eating my distributor cap center electrode - I was changing them every few runs.

This is not a case of more is better it is a case of if you have adequate spark to optimize the burn it is all you need. More will not help!

I have said my peace on this subject...........

The amount of internal resistance in the combustioon chamber at WOT to the spark will determine what works best for each application. As already pointed out electricity is like water, it will take the path of least resistance. If it is easier to jump the spark plug gap it will, if it is easier to jump across the air gap in the distributor cap to another spark plug wire it will do that also, hence cross firing and backfiring I have freind who has to run a .010 gap on a blown alcholol motor with 50 lbs of boost using single 44 amp mag to make the motor rev to 9800 RPM without missing They now change the coil wire several times a year as well as changing the rest of the plug wires at least once a season, that is with less than hundred passes a year

Why?..........care to elaborate?.......In truth, all the wide gap does is force your ignition components to work way TOO hard to jump that gap. It does ZERO to make any more power or fire the mixture easier. The big gap stuff is just an old wives tale from the days of points ignitions........Why, because points firing was ONE spark, so let it jump as far as it can and it has a better chance of lighting..........MSD, stands for MULTI Spark Discharge. Gap is meaningless. We run some REAL high cylinder pressure stuff at as little gap as .010. If it will light that, if will surely light your 10.1 street motor at .035 without issue

A friend of mine was running a 70 Mustang with a big block Kasse engine in it. He had a very good MSD system on the car. He was always changing either coil, coil wires, caps, rotors or cap. Couldn't figure out why he was going through so many ignition parts. I asked him what his spark plug gap was . He said .055. I recommended to him to close it up to around .032 to 0035. He said no , because that was where the car ran the fastest. Finally, he decided to close the gap up. The previous run he ran 9.19. With the gap opened he ran 9.19. The point I am making is why open the gap up if you are not getting a better performance. We are in the race section so why would we be worried about a better idle or gas mileage. Just my opinion. Not looking for an argument.

Sheldon

The only reason he closed the gap up was because he was doing something around the ignition while it was running and he got zapped, taught he was dead.

IN TRUTH, I already elaborated. You can't figure it out, not my problem. Check with your OLD WIFE, or gap your plugs where ever you want. You obviously don't understand the MSD concept of having the best of both worlds ( high voltage with a long spark duration ). BTW, MSD stands for "Multiple Spark Discharge". I'm sure your stuff will work fine with a point ignition and an oil filled coil with a .010" plug gap.

I read what you said, but I thought you might give some actual facts or results to back up your claim, as nothing you said made sense..........but obviously you don't understand ignition systems nor electricity. It's also been proven time and time again, that tighter gaps make better power and eat less ignition parts or a race car.

Fuel cars run two plugs, because they run two Mags and nitro is impossibly hard to light under boost. And they run really tight gaps

Pump gas hard to light......really?........Guess that's why it detonates so easily, because it's hard to light.

Oh, sorry I left out the "ple" when I stated that MSD stood for Multi Spark Discharge, but they mean the same thing