Spark Plugs

[The Dan]

You are a minority.

Your not running an ignition amp or sorts?

Any one else here able to run a 1.1mm gap with 20+psi?

No, only the standard PTU. Iridium plugs and factory ECU remapped.

The problem is that all of these people have this funny idea that they have to do something because everyone else is.

Why is everyone gapping their plugs to 0.8mm? Because the guy next to them told them to or told them it would fix their misfire.

Well good on them...it does fix their misfire but doesn't fix the actual problem.

The only reason I am a minority is because I setup the car right.

People ask me all the time why they should change to the splitfire coilpacks and I can tell you it's because of those very reasons. I can run 22psi boost with a spark plug gap of 1.1mm.

Splitfire coilpacks offer a 50% higher spark energy and maintain a more constant voltage even at very high rpm.

You cannot plug these in and tell me you can't feel the difference. Or see it on the dyno.

[T04GTR]

oh yeah, cdi 1.1mm on 1.5 bAR no worrries

[MANWHORE]

I agree with 3lit3_32

He's not saing that regappign is no good etc. He's just saying, if you hvae a problem with misfire, coilpacks are the best way to fix it. if you can't afford it, then regap.

He's just saying, people shouldn't automatically just jump up a heat range and regap for the sake of it, without any mods, or with just an air fitler or something.

Everything said in your first post is correct mate. I don't know how many times i've seen people say that skylines have come with all sorts of different stuff stock.

Edited April 5, 2007 by MANWHORE

[Cubes]

The only reason I am a minority is because I setup the car right.

With regards to 20+ psi... The only difference you have to many others is your running the stock ecu. The rant about it being a bosch fuel pump etc.... you know thats crap. lol

Possibly the stock rb20det ecu has 'better' ign. dwell etc settings. Quite possible the pfc's values are off a touch which causes issues.

Manwhore... 20+psi with a gap of 1.1mm is the recent discussion.

I'll quote from 3lit3's origional thread starting post....

Just a bit of a general guideline - If you are running 12psi or less, you shouldn't need any less than 1.0mm spark plug gap. Running 12-16psi ~ 0.9mm gap and 16-20psi ~ 0.8-0.7mm gap.

[The Dan]

With regards to 20+ psi... The only difference you have to many others is your running the stock ecu. The rant about it being a bosch fuel pump etc.... you know thats crap. lol

Possibly the stock rb20det ecu has 'better' ign. dwell etc settings. Quite possible the pfc's values are off a touch which causes issues.

Manwhore... 20+psi with a gap of 1.1mm is the recent discussion.

I'll quote from 3lit3's origional thread starting post....

That's why it's a general guideline.

For people who are using the factory coil packs then these are the more preferred options. If you upgrade to the splitfires then you can disregard regapping alltogether.....unless ofcourse the problem is not ignition. Read the sentence before the one you quoted of me and you'll see that I was referring to standard coils

Once again Cubes you have missed the whole point of the thread. I don't have anything against regapping plugs. The whole aim is to achieve the highest spark gap without compromising spark energy. By reducing the gap, you are just reducing the resistance across the electrode which means the coil doesn't have to build as much energy to arc across it.

Go ahead and regap your plugs. But only do it if it's required - not just because you think you have to. If you are going to regap them, actually spend some time finding the right gap. This might mean removing the spark plugs 5 times but you'll learn something in the process. If the gap you require is considerably less than factory specs and you aren't running extremely high boost, then consider WHY you have to reduce the gap that far and think about what you can do to improve it. If your car is overheating would you just keep topping up the water and never look for the problem? If the answer is no, then ask yourself why would you settle for weak ignition and just reduce the gap of the plug? Do it properly.

I have regapped plugs for many customers but it's not always necessary. I try to educate people but it doesn't always work.

[The Dan]

And why do I know the bosch pump comment is crap?

I think walbro pumps suck arse. Get the flow specs for the pump and try to tell me it even comes close to the bosch pump.

The 255L/hr pump works out to be something like 150L/hr once you hit 55-60psi rail pressure.

But who needs adequate fuel flow at high rpm, high boost?

[Cubes]

Once again Cubes you have missed the whole point of the thread.

No.. You've completely misunderstood.

Please re-read my previous post, I don't think you have anything against regapping the plugs.

With regards to 20+ psi... The only difference you have to many others is your running the stock ecu. The rant about it being a bosch fuel pump etc.... you know thats crap. lol

Possibly the stock rb20det ecu has 'better' ign. dwell etc settings. Quite possible the pfc's values are off a touch which causes issues.

What that says is....... yes.. there's many others with 'good' fuel pumps, 'good' fmic's, 'splitfires' but with the powerfc or other ecu (microtech). So the only 'real' difference is that your running the stock ecu.

So why can you run 1.1mm while others can't? Maybe its the ign dwell values, maybe its the ign dwell vs volts, maybe......?

And why do I know the bosch pump comment is crap?

I think walbro pumps suck arse. Get the flow specs for the pump and try to tell me it even comes close to the bosch pump.

The 255L/hr pump works out to be something like 150L/hr once you hit 55-60psi rail pressure.

But who needs adequate fuel flow at high rpm, high boost?

It will lean out.. Fuel supply method has NOTHING to do with poor ignition providing there is fuel there.

Gap plugs down because you run a walbro is what your post insinuates. I know you know thats not the case, which is why I said you know thats crap.

Guilt-Toy I believe could possible be on to something.. Airflow/VE. Small turbo's with poor VE due to their restrictive hotside combined with stock exh. manifolds could partially be the problem.

[Devils_Advocate21]

I think the main argument arizen here is the requirements of always bandaid fixing things whilst the issue could be resolved by fixing the source of the problem? Im sure thats whats trying to be said. Also I have got to admit one thing in saying this is that there is No doubt Dan can run these right gapped plugs of -11 (Factory settings) with splitfires coil packs attached to them is that no doubt dan has researched the right conditions for this to be operating in. Hence AFR's are most likely to be perfect: Too rich foul the plugs missfire due to poor connection (Hence regap) , too lean well sif you go down that path, And for the ""Modified"" non stock thats rubbish in a way as fuel and air are still added the same way to the combustion chamber if the afr is correct there should be no reason why you cannot run stock gapped plugs, Tuning would be another issue to why people go smaller gapped plugs but that said there Also has got to be a limit of a certain gap and heat range for what power to be produced. (contradiction to my previous comment) Maybe? But there is a limit on everything no matter what it is.

Extract from NGK site below ( http://www.ngkntk.co.uk/technicaltips/sparkpluggap.asp )

"Aways check that the spark plug gap is compatible with the engine manufacturers specification. A gap that is too small means that the spark duration will be very quick and the spark will be thin and weak. The consequences of this may be bad starting and high exhaust emission levels. This will result in an increase in fuel consumption. If the gap is set too large, the ignition system will not be able to cope with the demands and a misfire situation will occur."

The above mentioned site may clear alot of things up for many people

Not only i have to post this quote as this may add to the debate:

Since the gap size has a direct affect on the spark plug's tip temperature

and on the voltage necessary to ionize (light) the air/fuel mixture, careful attention is required. While it is a popular misconception that plugs are pre-gapped from the factory, the fact remains that the gap must be adjusted for the vehicle that the spark plug is intended for. Those with modified engines must remember that a modified engine with higher compression or forced induction will typically require a smaller gap settings (to ensure ignitability

in these denser air/fuel mixtures). As a rule, the more power you are making, the smaller the gap you will need.

A spark plug's voltage requirement is directly proportionate to the gap size. The larger the gap, the more voltage is needed to bridge the gap. Most experienced tuners know that opening gaps up to present a larger spark to the air/fuel mixture maximizes burn efficiency. It is for this reason that most racers add high power ignition systems. The added power allows them to open the gap yet still provide a strong spark.

With this mind, many think the larger the gap the better. In fact, some aftermarket ignition systems boast that their systems can tolerate gaps that are extreme. Be wary of such claims. In most cases, the largest gap you can run may still be smaller than you think.

And:...

5. Heat Range selection

Let's make this really simple: when you need your engine to run a little cooler, run a colder plug. When you need your engine to run a little hotter, run a hotter spark plug. However, NGK strongly cautions people that going

to a hotter spark plug can sometimes mask a serious symptom of another problem that can lead to engine damage. Be very careful with heat ranges. Seek professional guidance if you are unsure.

With modified engines (those engines that have increased their compression) more heat is a by-product of the added power that normally comes with increased compression. In short, select one heat range colder for every 75-100 hp you add, or when you significantly raise compression. Also remember to retard the timing a little and to increase fuel enrichment and octane. These tips are critical when adding forced induction (turbos, superchargers or nitrous kits), and failure to address ALL of these areas

will virtually guarantee engine damage.

An engine that has poor oil control can sometimes mask the symptom temporarily by running a slightly hotter spark plug. While this is a "Band-Aid" approach, it is one of the only examples of when and why one would select

a hotter spark plug.

Thankyou for information sourced from ( http://www.ngksparkplugs.com/techinfo/spar...&country=US )

Im sure they have the money in the r+d on the issues ? Although i have got to say better ignitions systems ie: Splitfires or MSD ignition modules would help but are expensive and long term fixes for running smaller gapped plugs due to there ability to be able to produce a better spark These are most likely where the issues are caused by at the end of the day

Cheers Adam

[FineLine]

Well I had a pod and changed exhaust, guess what.. misfire straight away, never misfied before

Just finished installing BPR6ES-11 plugs, gapped them down to .8, perfect, didn't worry about taping the coils as I couldn't see anything wrong with them

Car now pulls strong all the way to redline

Just did the exact same plug swap and gap change this morning. Instantly cleared up a nagging miss under load in 2nd. Couldnt be happier with the result.

[Devils_Advocate21]

Added information above to my previous comments this will clear and hopefully end the debate and arguements.

Thankyou and happy merry easter

Adam

[siddr20]

lol is flat spots same as misfires? ok ok i know its not the same!!

Coz to be honest, with full exhaust, pod, more boost, stock cooler, stock ecu.. I had flat spots everywhere!! really sucked driving.. thought i turn boost down.. didnt help (1.1 plusg gapped at the time)

So i changed plugs one day to 0.8.. biggest smile ever.. car felt like a 180kw car

Heat range of 7 may i add.. Since then, no problems at all.. but you can still feel a few flat spots, but not as much as before..

At next oil change, im going to go for a heat range of 6.. Test that out and see what happens!!

Maybe even buy standard 1.1 plugs and see what happens..

guess my problems is that i need a tune..

I dont think i have ever experienced missfires in my car.. only flat spots even runnin at 1.1 gapped plugs..

or could it be that those plugs where old? and owner from japan didnt replace them?

Hope that helps..

but maybe this help a few ppl:

Standard boost = BCPR6ES – 11

12 psi = BCPR6ES – 8

Up to 19 psi = BCPR7ES – 8

Over 19 psi = BCPR7ES – 6

EDIT: ohh another reason why most people regap there plugs to 0.8 is because the tuner says so..

I know my friend who got his car tuned got told to regap his plugs to 0.8 before coming in..

So now hes passed that info onto me.. Tested it and actually felt a huge difference.. Not becuase i had mis-fire issues but to band-aid flat spots issues, till i get a pwer fc or similar..

Edited April 6, 2007 by siddr20

[subzeroR33]

I run a microtech, MSD DIS 4 ignition pack with ford coils on 22psi.

I was runing irridiums bkr5es-11 somthing like that, and after a while it started missing on high boost.

My tuner closed the the gap to 0.8 and said i should change the heat range to a 6 or a 7 also my map sensor could not handle the 22psi. So he reduced the boost to 19psi, all runs good now.

Im now using BCPR6ES run fine.

3lit32 i know you are just trying to give some good advice to peolpe, but if they dont want to listen thats there problem.

[Cubes]

I'm listening. I'm currently running 0.9mm gap as that is all mine allows.

I run a good intercooler, inlet temps are down, good fmic, good exhaust.... standard plenum standard exh. manifold.

Hence my suggestion that Guilt-Toy was possibly more so on the mark than the fuel pump suggestion.

3lit34 Give some tips on what can be done apart from silly fuel pump suggestions.

[dangerous_daveo]

I'm listening. I'm currently running 0.9mm gap as that is all mine allows.

I run a good intercooler, inlet temps are down, good fmic, good exhaust.... standard plenum standard exh. manifold.

Hence my suggestion that Guilt-Toy was possibly more so on the mark than the fuel pump suggestion.

3lit34 Give some tips on what can be done apart from silly fuel pump suggestions.

The fuel pump/filter came up because of people complaining of a miss... Which could be the cause of the miss in some cases. Just to clear that up.

But its a fairly valid point Daniel brings up. Why bandaid the problem? Many people are happy to go spend lots of money on other things, new seats, new wheels, new paint, body kits etc. But arent prepaired to fix a problem such as this properly.

That said, there are so many vairiables it I would think it makes it fairly tricky to pinpoint the problem on each individuals car.

[Devils_Advocate21]

I still believe my quotes that i have above are pretty much explains everything if you read back a bit cubes

[tek_01]

just to add,was running 12psi now im running 14psi on standard coil packs and 1.1mm platinum plugs without 1 miss and have had it like that for approx 6 months

[PSI Parts]

This might give you a good guideline as to whether the plugs you are using are functioning correctly.

[T04GTR]

ok. well i just had to re-gap my plugs down to .8. cos im using a mitsubishi gto coil; pak. its abit mor compact. but anything over 1 bar it misses.

i used to have mazda rx7 twin coils. but they are massive and i cant fit them neatly on the firewall.

ithink i will have to get propper cdi coils coz i think the charge time is to high on the mitsubishi ones.

id love to use the mazda ones. (i can get a 3 inch long spark from them in the air )

[OVL-747]

nissan designed their system to be run at 10psi or whatever the factory setting is.

if you intend on running 20+ pound then you ultimately need to change a lot of stuff.

i agree with a few views from different ppl in this discussion , but your ignition system is only as strong as its weakest link.

in saying that , that goes for you driveline , fuel system , cooling system etc too.

[R32-PSH77]

Just to share my experence

i have had a misfire problem since the day i bought the car.

started of bog stock, 10psi stnd everything it was running PRF5A11 so heat range 5 - 1.1mm gap

(misfired all over the place) worst feeling ever.

Changed to iridium BCPR6EIX-11 was good for few weeks, the along cam the exhuast and fmic

this raised boost to around 11psi.. and the misfire came back

changed fuel pump to a bosch 023 largest internal bosch pump u cant get. almost 300lph still misfire.. didnt chnage a thing.

Finally changed to some BPRC6ES (0.8mm gap with V grouve) ran 14.7psi (with new turbo ect) and No misfire

so the gap helped. i have actually done the high temp silicon trick to the coil packs.. worked a tad better.. deffintly the spark plugs that did the job.

however still awaiting a retune. so possible will all be running nice because 16psi+ shows slight misfire again.

Im going to get some splitfires.. but untill i save 600 bucks. im just going to run around with 24buck plugs. so i dont feel like im hitting a revlimiter from 2,000rpm to 7000rpm LOL

My 2cents

Adz