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Spark Plug Gap

Dee23

Dee23

New member
1. Autolite 1-3 heat ranges colder recommend to gap from .052-.060 (for the 1-3 heat ranges colder). A colder plug is meant to help transfer heat from the combustion chamber so a bigger gap would contribute to that but that gap would put more load on the primary ignition system to make that gap jump. Any other reason y they recommend this large gap?

2. I been using Pulstar Iridiums for a couple of years now and they recommend on turbo & s/c applications to gap at .025. I personally always felt that was damn to small of a gap so i left it at .036. now the heat range is 5-7 (equivalent to NGKs 1-12 heat range 12 being the coldest) so Pulstar 7 oppose to NKG 12 is 5 heat ranges hotter (NKG is 5 heat ranges coolder) so im thinking Pulstar iridiums are like 1 heat range colder compared to a OEM stock plug. These plugs are much powerful than most, about 1-2 heat ranges colder than stock, and I know the more power u make the less of a gap u would need but y so small at .025? I mean its not a s/c 1970 Buick GS(hypathectically) with 13:1 compression ratio, its a 3.8 s/c with 8.5:1. Much less power but the plug instructions dont indicate how much power, it just says s/c or turbo gap at .025. I think its to small, do any of u have any thoughts on this?
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Because our ignition system can handle it.

So the plugs are good, but you have to run no gap? I smell BS.

Also run the right heat temp for your particular setup. So see how the plugs burn and buy different plugs based on that.
 
Yeah, I was think about tring the Autolite 605s. These pulstars are the **** though, they have a capacitor in them that stores power(spark) and then releases, creating a much stronger spark.

I mean i have no problem with these Pulstar Iridiums, I just dont understand why they recommend a .025 gap for s/c motors. I just think thats to small but i have thought about running at .025 to see if there were and peformance differences(in my favor) but beings though these plugs are iridium I didnt want to keep gapping them possibly messing up the center electrode.

Been at .036 for the longest, but i still wonder what it would feel like if i gapped them at .025....hmmmmmmm
 
One plug recommends to gap at .052 and the other plug recommends .025. Im tryna figure this out. Maybe bc the pulstars have the capacitor, generating more power. hmmmmmmmmmm, I just know .025 is pretty damn small....
 
please dont fall for that marketing gimmick bullcrap. seriously.

just buy a set of plugs and gap them at .060"
 
LOL Pulstar.

Get bent.

Buy some AL605's, gap them at .050" because there is less chance of a misfire.

/done.
 


Sounds like you work for Pulstar or something. Don't believe everything you hear. I would stick with autolites.
 
So if they store energy, you must not be getting the correct timing advance.

Meaning you're missing fuel economy and power.

Also causing unnecessary wear on your exhaust valve/seat.
 
I've ran autolite app605s on both my 04 gtps and I can watch misfire data on my tech2.... not a single misfire.. ever.. not even in history. I gap'd them at .060

Sent from my Galaxy SIII on Tapatalk 2
 
By the way capacitors in the plugs is just ridiculous. Should almost do the exact opposite of what they think a capacitor would do in a high voltage spark system...I would almost lean towards it causing a delay in when the spark should fire.

I'm an Auto Electrical repair and diagnoses tech. ASE & State Certs if that helps back up my theory.

Prove me wrong I suppose. lol

Sent from my Galaxy SIII on Tapatalk 2
 


Thanx guys for the response. When I said the capacitor stores power, I was referring to it happening only when you shut the car off. It pretty much helps with the cold cranking in the morning.

I've been running Pulstar iridiums for a long time now and are the only spark plugs i've used in years. I've just never understood how a gap at .025 is beneficial in any kind of way. They say .025 is only for s/c & turbo charge motors, so Im assuming the power that a s/c & t/c makes that when its used with their plugs which they claim are stronger, The gap any bigger than .025 is not needed.

I never bought into that gap size and i remain around .040, but i do plan to try out the AL605s. One heat range should be engouh for my setup. But .060 I think would still be to much, and .050 should be good enough for a complete fuel burn.

Hey guys, im surprised yal never heard of the Pulstars iridiums or at least fell for their gimic.....LOL
 
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The cap does nothing, if its even there.

because coppers work oh so well.

Side gap and index your plugs for more power.

So what power adder do you have? What sort of boost are you running?

Because honestly, if its a 3.4, 0.060" is fine. You're supposed to run the largest gap you can, not smallest.

You go smaller to help prevent blow out from boost.
 
Agreed, have you checked out the Pulstar iridiums to see why they recommend s/c & t/c applications to set the gap at .025? Im still seeking for a reason for this gap size, thats the only reason I made this thread..... Most people I talk to never even heard of Pulstar iridiums.....weird
 
In most applications when you add boost to a high compression engine that ends up being the recommended gap.

Even our cars with 15+ psi people tend to run smaller gaps.

However for mostly stock cars, mostly stock gap is ideal.

I did answer the question in my previous post. To prevent spark blowout.
 
Yeah i read your last post. But what im tring to figure out is if .025 gap is ideal for my setup. Pulstar just says to use that gap for any s/c application. It doesnt say how much power or the exact amount of compression you need for the .025 gap to be affective/beneficial.

In other words, since im not making that much power and my compression isnt that high, I shouldnt use a .025 gap correct (even though they recommend that gap for s/c aplications when using their plugs)???????????

And based on what you said, people running 3.0"-2.55" pullies should be running smaller gaps right? (opposed to the NGK/AL gaps at .052-.057)? Im tryna understand this, thanx for helping me out....
 


I would ditch those plugs and get normal plugs, then gap at 0.060".

Is that what you're looking for?

The age/condition of your coils and wires will also factor into how much gap you can get away with.

Definitive answer on running gap down there? No clue. Never been there myself.
 
You answered your own question.

Since no s/c car is the same how can they have such a broad gap size when they know nothing about the vehicle other than it's got a blower.

On the other hand gm spent millions developing the vehicle and it's ignition system which has changed little on the 3800 over the years.

In past experiences just go with people who know A LOT about your vehIcle (ex. A forum) see what they recommend and KNOW what's ideal. :)

Sent from my Galaxy SIII on Tapatalk 2
 
Thanx you guys, and Matt I appreciate your time. i'll probably do what you recommended, go with some normal plugs bc these Pulstar iridiums requiring .025 gap just dont make sense to me.....Thanx guys
 
Heres a pic i took a while ago of those Pulstar iridiums that require a 0.025" gap on S/C or Turbo applications.....Cool plugs but i didnt really like them
SL381399_zps6853823d.jpg
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