[F87source]

Originally Posted by chris719

Cause or effect?

It seems like most misfire problems we see here are people using NGKs on Stage 1 and go away with stock plugs.

It's actually not the NGK - to an extent.

From what I have seen it's the gap that causes these misfires, and when they go to a larger gap (generally closer to stock) the misfires go away. These cars don't seem to sensitive to colder plugs, so the NGK's play no part in the issue.

Now here's the caviot, I have heard issues come from the poor QC of the NGK plugs, that's the only time when I see the plug being at fault, and according to AmuroRay QC problems on NGK plugs are way more common than on Bosch plugs.

[chris719]

Originally Posted by F87source

It's actually not the NGK - to an extent.

From what I have seen it's the gap that causes these misfires, and when they go to a larger gap (generally closer to stock) the misfires go away. These cars don't seem to sensitive to colder plugs, so the NGK's play no part in the issue.

Now here's the caviot, I have heard issues come from the poor QC of the NGK plugs, that's the only time when I see the plug being at fault, and according to AmuroRay QC problems on NGK plugs are way more common than on Bosch plugs.

There are a ton of counterfeit NGK plugs out there, so I wonder if this is part of the issue as well.

[F87source]

Originally Posted by chris719

There are a ton of counterfeit NGK plugs out there, so I wonder if this is part of the issue as well.

It very well could be, that's why no one should ever buy plugs off of eBay, or non authorized resellers.

[Track/S]

Originally Posted by F87source

1) IDK how you came to this conclusion but even your statement itself is a contradiction: "the M4 GTS has the same power as the standard M4, +40 HP is thanks to water injection". What does that even mean? Does it have the same power or not, you can't say it has the same power and then it has 40 more horse power right after, that makes little to no sense.


In reality the GTS doesn't make the same power as the m4, it makes way more and that is a concrete fact, is it thanks to water injection? Yet but the it is undeniable that the GTS makes more power. Next misconception water injection alone doesn't increase power... You can spray water into a stock m4 and if you don't make a single tuning change the car will adapt to the water injection (you technically don't need to tune if you are just spraying water, because the water itself should be fully atomized in the charge pipe thereby displacing air, and so the air being displaced is measureable by the o2 sensor and the car can adapt by default, this is how the car adapts when running in high humidity or during a rainy day - no tuning needed just make sure the meth kit is truly progressive i.e. aquamist) and it will make zero additional power. Adding water has nothing to do with increasing power, even adding methanol doesn't increase power... The key is knock supression.

Water injection decreases IAT's and cools the flame front and any hot spots in the cylinders thereby supressing knock. This lets the car push harder by adding more boost and ignition timing. This is seen in the GTS because it targets 21-22 psi of boost, vs. 17-18 psi of a stock m4. So you are completely wrong on your analysis of the situation in regards to the GTS.

So what can we conclude? The power level and cylinder pressure isn't the cause of failure - because the M4 GTS which makes more power and runs more boost is just fine. Is it EGT? Again there is no conclusive evidence that Stage 1/2 (with a tune that isn't lean) over heats these plugs - if you're melting plugs you're melting pistons right after, so EGT isn't an issue either. I have seen so many images of the stock bosch plugs after tuning and they look fine. None of them were glazed over due to running hot. Is it "EMP", and by EMP I assume you mean eddy currents and electrical noise, I highly doubt this is the case because the IGBT in the Ecu and the coil packs would be toast if this was the case long before the spark plugs were.

So you haven't given any concrete evidence to counter this, you're just giving opinions that don't even seem to be common enough to be credible. This is just like when you said oil has no link to carbon build up with zero concrete evidence, except your own limitied visual observations that have no scientific merit. Then you try to draw major conclusions off a small and limited sample size and refused to accept scientific studies done by countless others that do link carbon build up directly to to the oil and NOACK/SAPS ratings.


2) There are 2 part numbers for spark plugs on the m235ir, one of them is Bosch: https://www.realoem.com/bmw/enUS/sho...diagId=12_1926

The GT3 and GT4 cars do use NGK's, but these are motorsports cars under race conditions - which may justify the requirement of a colder plug. Because I doubt the NGK's are "tougher" because I've seen them crack and fail too. Or NGK could be a parts sponsor, since they sponsor alot of motorsports cars - they sponsor ferrari in F1 for example.


So there still isn't definitive evidence that the stock plugs will crack or fail when tuned
over stock power levels on a street car. What you claimed is that the stock plugs couldn't handle the power bump and would fail, and you still provided no definitive evidence. You said that you've seen stock plugs crack, well I too have seen NGK's crack - what's your point? You literally can't draw any conclusion based off of such a limited data set. This cracking could be user install error, or another issue like very agressive knock that broke the plug. In either case it just doesn't make sense to blame it on the plug. Plug's don't just break by themselves, so there must have been another root cause.








Either way OP's engine is blown. So there isn't much left to say except hope that it isn't catastrophic and limited to just piston damage.

Bro, too much text, m4gts has 40hp more at the moment the water is injected, and it doesn't always inject, only when it exceeds xx degrees of IAT, therefore it almost always goes with 460hp.

Even easier, the 500 hp is not obtained by increasing turbo pressure, but by cooling the combustion chamber, therefore the oem spark plugs suffer even less.

Originally Posted by chris719

What gap do you run typically for stage 1?

I always leave them at 0.022.

[F87source]

Originally Posted by Track/S

Bro, too much text, m4gts has 40hp more at the moment the water is injected, and it doesn't always inject, only when it exceeds xx degrees of IAT, therefore it almost always goes with 460hp.

Even easier, the 500 hp is not obtained by increasing turbo pressure, but by cooling the combustion chamber, therefore the oem spark plugs suffer even less.



I always leave them at 0.022.

Again you're completely wrong...

https://f80.bimmerpost.com/forums/sh....php?t=1262417

1) Injection start is load and RPM based not strictly iat like you said...

"If the engine is operated in a load range (full load) and engine speed range (>5000 rpm) that justifies water injection, the DME requests this."

Bmw also stipulates volume iinjected is dependent on the ecu and various other running parameters.


2) The technical documents also mentions BMW operates the engine with higher charge pressures and earlier ignition. So again you're wrong.

Several press sources say its a ~4psi bump: https://www.bmwblog.com/2016/09/14/t...ok-bmw-m4-gts/


The M2CS, M3Cs, and M4CS are all making Stage 1/2 power level and no water injection, and running on the Bosch spark plugs without issue. This further refutes your narrative that the stock plugs can't handle these running conditions.


3) You do realize that air density doesn't increase enough for there to be a 50 HP gain right? The car is also load based tuning, so when the iat's get that cold it will alter engine parameters to keep the same load. So without running the engine harder you will not make more power.



Btw gapping down without cause is how you trigger misfires and incomplete combustion. Maybe that's why you are seeing alot of broken plugs.

[Track/S]

Originally Posted by F87source

Again you're completely wrong...

Again? Lol, but ok.

[imperfectluck]

F87source not to digress the convo too much from OP’s thread but you mentioned gapping down to 0.022 being problematic and I’ve done that on my last F30 n55 when I had it stage tuned and now just recently did so on my F87 stage e30 yesterday. Haven’t been able to push the car yet but folks at the shop swear by that gap standard and I had followed the same per BM3 suggestion a while back.

If you’re currently tuned, what gap have you been running? I’m on stock plugs btw, tried the NKG on the F30, wasn’t feeling the colder step as the car did run rougher and you’ve been following these threads for a while to be a wealth of knowledge on the subject matter.

[F87source]

Originally Posted by imperfectluck

F87source not to digress the convo too much from OP’s thread but you mentioned gapping down to 0.022 being problematic and I’ve done that on my last F30 n55 when I had it stage tuned and now just recently did so on my F87 stage e30 yesterday. Haven’t been able to push the car yet but folks at the shop swear by that gap standard and I had followed the same per BM3 suggestion a while back.

If you’re currently tuned, what gap have you been running? I’m on stock plugs btw, tried the NKG on the F30, wasn’t feeling the colder step as the car did run rougher and you’ve been following these threads for a while to be a wealth of knowledge on the subject matter.

You technically can't "swear by" any arbitrary gap size, because it varies from car to car, coil pack health, tune, conditions etc. So swearing by a particular gap size without any data to support it is just ridiculous. So unless your shop has spent millions of dollars testing spark plug gaps in all running conditions, all climates, all possible spark energies as the coil degrades, they cannot make a one size fits all call like that.

Ideally you should run the stock gap size - which has been tested by BMW and Bosch vigorously under all these running conditions all over the world, and then gap down only when you need it (i.e. when experiencing spark blow out). This is how it should be done, run as large as possible and move down as data logs show you that it is required. Not guessing some random number because one feels smaller is better - because it isn't.


So why would you want to run a gap size as large as possible? Because you want to promote complete combustion, the larger the spark the large the "ignition area" and the larger the ignition pocket can be to burn all the fuel in the combustion chamber. If you go smaller gap, that ignition pocket gets smaller and you start to experience incomplete combustion. The only reason one would gap down is to prevent spark blow out, because the smaller the gap the harder it is to blow out the spark. However gapping down to stop spark blow out is only a band aid solution, in reality you should get stronger coils to retain the gap size.


I have helped alot of people on here who got rough idles and misfires due to the gap size being too small. So that's why I'm suggesting staying stock, and gap down only when needed, take feedback from your car, not some arbitrary one size fits all suggestion, because there is no such thing as one size fits all without massive rnd.

[imperfectluck]

F87source I hear you and it begs me to ask why would PTF suggest this specific gap range here? I understand the logic of starting at stock gap and going smaller if needed though I find it odd coming from a platform that develops tunes to hear otherwise which is why most folks just gap down and go to town.

Reference

[F87source]

Originally Posted by imperfectluck

F87source I hear you and it begs me to ask why would PTF suggest this specific gap range here? I understand the logic of starting at stock gap and going smaller if needed though I find it odd coming from a platform that develops tunes to hear otherwise which is why most folks just gap down and go to town.

Reference

No idea why they recommend that, but it's way too agressive of an approach. Maybe they anticipate alot of people don't want to do any of the leg work to dial in their car properly but idk.

Either way like I've said before I've diagnosed a lot of spark plug gap induced issues on this forum alone. So there's that.

[chris719]

Originally Posted by F87source

No idea why they recommend that, but it's way too agressive of an approach. Maybe they anticipate alot of people don't want to do any of the leg work to dial in their car properly but idk.

Either way like I've said before I've diagnosed a lot of spark plug gap induced issues on this forum alone. So there's that.

I agree. I assume the stock gap for M2 CS Racing is the stock NGK gap which is 0.030" IIRC.

[AmuroRay]

I’m running NGKS at out of the box gap. I don’t know what the obsession is with gapping down, or even changing from OEM. I did it because everyone else was and it provided nothing.

[chris719]

Originally Posted by AmuroRay

I’m running NGKS at out of the box gap. I don’t know what the obsession is with gapping down, or even changing from OEM. I did it because everyone else was and it provided nothing.

People just don’t understand and like with many other things, messing with something makes them feel better.

[F87source]

Originally Posted by chris719

People just don’t understand and like with many other things, messing with something makes them feel better.

+1


There's always a train of thought process out there that after market is always better than stock, so there is a huge rush to replace all stock parts with aftermarket.

While for somethings that may hold true (engine oil - replacing the FE garbage for non Fe oils) there are somethings that are better stock (diff oil).