Jump to content
SAU Community

Recommended Posts

Hey guys,i changed my own spark plugs today for the 1st time,and apart from the fact the car is still Running:).....im not so happy.

I previously had some ngk's gapped to .55mm and my car was running fine at 10psi..,this was done by a workshop, and they fixed my missing issue.

But i decided to change as i thought .55mm was quite low for a car with jst pod/zorst and fmic running 10psi.

So i went and brought some ngk's that alot of ppl on this forum use (dont know the gap rating, but the outlet store said they are close to 0.8mm)

I installed using a guide posted on this forum (which greatly helped), and after all had been done, i took the car for a spin, and anything over 5500rpm would make the car pop like mad!

so im thinking the plugs arent gapped properly?

few things id like to ask

1) how good are the spark plug gap gauges(wire ones)

2) when removing sparkies should i spray compressed air around the area and be done with it?

3) Do these spark plugs have to be torqued down?, ive been using a rathchet to tighten firmly.....is this advised?

thanks in advise, i may have to do this all over again in the wekend, for now ill go back to stock boost:)

  • Replies 41
  • Created
  • Last Reply

Top Posters In This Topic

Hey i think they just gapped them to .55mm to be sure that it wont ping/pop anymore, as it was 1.1mm beforehand.....so i have nevertried .8mm.....and it seems that the ones in my car at present may not quite be 0.8mm(i never had any tools to measue:(

one other question though.....whats the best way to clean the area arounf the spark plugs???using something like Dust off (can of compressed air thats used most often for cleaning electrical components keyboards etc....)

i'll be having another go soon.

I was reading some other threads,and it seems that i should have cleaned the area before even removing the plugs(incase of anything going into the chamber).......i didnt do this....could this be a cause of the problem?i hope i havent done something to my engine.

leave the plugs in when cleaning the area!

as mad082 said, if they were gapped to 0.55, think there will be a coil pack problem or something if its missing with 1.1 or 0.08!

been there and had the same issue

Just in case you doubt the first two recommendations...

If your car is missing with 0.8mm gap then it is time to replace you coil packs. If you do decide to replace them, you will be much better off buying Splitfire coil packs.

So double check your gapping, just take the plugs to your local mechanic, and make an educated decision.

whoa, hold up the love boat, if you just popped your spark plug changing cherry, i would go back and remove the plugs, there is a very real chance you may have cracked a plug. they can be quite delicate. also double check the gaps.

i have experienced this with even a well known "performance" shop (bob romano's) having cracked a plug in my 25 for me to discover. it's not hard to do even if you are experienced!!!

i have experienced this with even a well known "performance" shop (bob romano's) having cracked a plug in my 25 for me to discover. it's not hard to do even if you are experienced!!!

i never heard of that. i dropped 2 of mine before i put them in. 10,000k's at boost between 12 and 14psi and no problems yet. i know they can be broken, but i wouldn't say they are delicate.

Edited by mad082

how can you tell if youve cracked a plug, and how would it happen?overtightening?

also it seems everyone thinks my car is missing at 0.8mm gap, i dnt actually know the gapping on my pressent plugs, and the last ones i had went from 1.1mm down to .55mm, we never tried .8 back then.

So i think my coils maybe ok

if it is missing at 0.8mm gap then there is a spark issue, and you aren't running enough boost to have issues with a 0.8mm gap unless the coil packs are lazy. 0.55mm gap is extremely small! much too small for low boost.

Spitfires are a direct replacement..

What car/engine? I'm assuming RB25 as your listing 10 psi as a mod.

Do you have any aftermarket engine management?

Mine had the same issues with .8mm plug and the same mods.

Coilpacks were repaired, made a difference, but still mild pop. Really bad on cold nights.

Got the car tuned with some aftermarket managment, works a treat! More power too. Never popped again. On researching it I found that the issue was just the mixture was getting to rich to ignite.

Alot of people on here have replaced the coil packs and the problem goes, however, alot of people have also replaced coils and the issue had not go away as it was something else, like rich mixture...

they should not be too tight. especially with an alloy head it's very easy to stuff the head by overtightening. there are torque specs in the shop manaul and it's very low.

you should have checked all the gaps before installing them. also, no one has asked yet. what heat range are they?

always clean around the plugs BEFORE you remove them as the whole point of this is to stop sh1t dropping down into your engine.

cheers, ill confirm they are gapped right and let you guys know.

Btw no one ever told me how tight the sparkies should be tightened?

According to the NGK website, they should be torqued to around 20 lb/ft (which isn't actually all that much). And they should be installed into a COLD engine (well, torqued down when the engine is cold).

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • Cool to see you're on the forum man, think you've met my twin brother a few times (Brent).
    • Yeah everyone always seems to refer to them as S13 wheels however they came on R32 Skyline, A31 Cefiro, C33 Laurel etc., and also came polished diamond cut or painted depending on the model. Congrats on your GTS purchase! I'd personally leave it NA.
    • In this thing about this 100% renewal energy stuff I hear no one really talking about anything other than power and fuel really Power and fuel, whilst being a huge part of how we use the billion year old Dinosaur juices, are only 2, of the probably thousands of things that we need to use it for in the chemicals industries for making nearly everything we use nowadays I'm all for a clean planet, but if we want to continue to have all the day to day appliances and stuff that we rely on everyday we will still need fossil fuels Whilst I do love science, and how it can bring innovation, there's really a limit to how far it can go in relation to "going green" As for EV's, unless your charging of your own solar panels, it isn't helping the environment when you consider the the batteries, the mining processes required,  the manufacturing process required, and how long a batteries (read: the vehicle) lasts long term If I was supreme dictator of the world, I would ban the use of sugar for fizzy drinks and food additives and use that for ethanol manufacturing, petrol engines would be happier, and people would be alot healthier  Disclaimer: Whiskey manufacturing would still be required, so says the supreme dictator of the world Same same for all the vegetable oils that get pumped into all our food, use that for bio diesel Disclaimer: the supreme dictator would still require olive oil to dip his bread in This would take some of heat off the use of the use of fossil fuels which are required for everything we use, unless you want to go back to pre 1800 for heat and power, or the early 1900's for plastics and every thing else that has come from cracking ethylene  Would I be a fair and just dictator, nope, and I would probably be assassinated within my first few months, but would my cunning plan work, maybe, for a while, maybe not Meh, in the end in an over opinionated mildly educated arsehole typing out my vomit on my mobile phone, which wouldn't be possible without fossil fuels And if your into conspiracies, we only need the fossil fuels to last until a meteor hits, or thermonuclear annihilation, that would definitely fix our need for fossil fuels for manufacturing and power issues for quite some time  Meh, time for this boomer to cook his lunch on his electric stove and then maybe go for a drive in my petrol car, for fun    
    • It really helps that light duty vehicles have absolutely appalling average efficiency due to poor average load. Like 25% average brake thermal efficiency when peak is somewhere around 38% these days. So even a 60% BTE stationary natural gas plant + transmission and charging losses still doing much better with an EV than conventional ICE. And that's before we get into renewables or "low carbon nonrenewable" nuclear which makes it a no-brainer, basically. In commercial aircraft or heavy duty diesel pulling some ridiculous amount of weight across a continent the numbers are much more difficult to make work. I honestly think in 5-10 years we will still be seeing something like the Achates opposed piston diesels in most semi trucks running on a blend of renewable/biodiesel. Applications where the energy density of diesel is just too critical to compromise. CARB is running trials of those engines right now to evaluate in real world drayage ops, probably because they're noticing that the numbers just don't work for electrification unless our plan is to make glorified electric trains with high voltage wires running along every major highway and only a token amount of battery to make it 30 miles or something like that after detaching. Transport emissions is not insignificant especially in the US, but yes there's a lot of industrial processes that also need to be decarbonized. I agree the scale of the problem is pretty insane but EDF managed to generate ~360 TWh from their nuclear reactors last year and this is with decades of underinvestment after the initial big push in the 70s and 80s. I don't think the frame of reference should be solar-limited. France is not exactly a big country either. Maybe it doesn't work everywhere, but it doesn't have to either. We just can't live off of fracking forever and expect things to be ok.
×
×
  • Create New...