[Jayrhee7]

Here's my list of upgrades I'm having done:
• CSF FMIC
• FTP Boost Pipe
• FTP Charge Pipe
• MST V2 Turbo Inlet Pipe
• Active Autowerke Catted DownPipe
• TurboSmart Dual Port Diverter Valve
• NGK 97506 (Gapped at 0.023)
• BootMod 3 Stage 2 OTS 93oct

My question is, I understand that Pro Tuning Freaks recommends the NGK 97506 spark plugs gapped at 0.022-0.023, which I have, but I remember hearing from some people that they have gaps of 1. Something....I'm amateur when it comes to tuning and spark plugs, so do you think the spark plugs that I have now are good enough??

[F87source]

Stock plugs and stock gap are fine. It's a common misconception to always run smaller gaps for no reason, read your plugs and logs to see if you need to make adjustments that's the only sure way to know.

For example ZM2 ran a reduced gap and had rough idling issues but upon increasing gap size to near stock that went away. Because the smaller your gap the more chance you will have of incomplete combustion and rough idling and misfires.

[nioh_lbbm2]

unless you're having a specific problem right now stock plugs are fine as F87source said above.

[F87source]

Here is a spark plug related quote from Justin aka Twisted Tuning whom I personally deem to be the best tuner for this platform - as he owns all the engines he tunes so he experiments on his own cars and not customer cars and thus has no history of blowing engines. He also works with MHD on developing their tuning platform so he knows what he's doing - along with offering custom wmi tuning with the torqbyte hardware.

Anyways that was a bit off topic but here is the quote:

Just recommending someone go to a one or two step colder plug because of a changed tune is not best practice. Poor combustion and misfires can occur.
The stock heat range in the N55 is fine to 700whp or so. One step colder than N54 stock. And the same heat range as nissan GTR stock plugs. GTRs run the stock heat range to 800whp or so.
The old recommendation of one step colder per 100whp is also not accurate. I mention this because ive seen it spewed on a lot of these groups. By that recommendation people would be looking for 6 step colder plugs in some cars.
Also, which is a slightly different topic (has nothing to do with your post) but people need to stop immediately recommending .018 plug gaps just because a car is tuned.
Ideally you want the largest gap possible for a setup that promotes complete combustion without blowout (failure of the spark to jump the gap).
Long story short.... proper spark plug recommendation should come from reading the plugs for a specific setup. Not a blanket recommendation from something you’ve seen people do.
IE- my A90 supra for instance. I’ve seen some tuners already recommended colder plugs or gapped down plugs for immediate process after tuning. Well, my car... stock plugs, stock gap. At over 700whp and 720wtq and reading the plugs show no issues. And the car has not skipped a beat or misfired at all."

[Jayrhee7]

Originally Posted by F87source

Here is a spark plug related quote from Justin aka Twisted Tuning whom I personally deem to be the best tuner for this platform - as he owns all the engines he tunes so he experiments on his own cars and not customer cars and thus has no history of blowing engines. He also works with MHD on developing their tuning platform so he knows what he's doing - along with offering custom wmi tuning with the torqbyte hardware.

Anyways that was a bit off topic but here is the quote:

Oh goodness....now I'm a little worried I have to check on plugs. My car is currently in the shop right now having all the parts added on to it, and since my car was already overdue for a spark plug change, I just threw in the NGK's gapped at 0.023 should I give them a call tomorrow morning and tell them to replace with OEM plugs instead???

[ZM2]

I think you’ll be fine with the NGK’s, but my car is happier with the gap at 0.026”.

[F87source]

Originally Posted by Jayrhee7

Oh goodness....now I'm a little worried I have to check on plugs. My car is currently in the shop right now having all the parts added on to it, and since my car was already overdue for a spark plug change, I just threw in the NGK's gapped at 0.023 should I give them a call tomorrow morning and tell them to replace with OEM plugs instead???

Don't worry about it just relax no need to rush, your car won't get a blown engine because of poorly gapped plugs you will just have poor performance if indeed your car doesn't like plugs gapped that tight. Some cars can tolerate it some cars can't that is why you have to look at your plugs on an individual basis and look at your logs then make the decision of what gap to use.


Imo if it is already done I wouldn't waste money doing it again, drive the car gently when you get it back to see if the plugs are causing a weird idle or misfire. If you do get misfires stop pushing the car hard immediately to avoid issues then pull the plugs out and open the gap up to stock size. Then the next time you do plugs you don't have to waste like $20 on NGK 2 step colder plugs, just buy the oem bosch ones from FCP for $5/plug and install them as they are already pregapped so no need to fiddle with gaps.


I can't remember if these plugs are single use due to the crush washers but if they are then you will need new plugs if you do have to pull them out.

[cookiesowns]

The biggest thing people forget to mention is plug reliability. The bosch plugs are known to crack the ceramic ( outer ) under higher heat/combustion loads. Especially on the hot v S63 V8's.

I personally went to 95706 as I intend on running E85 which has a faster flame front in which the colder plug will help with reliability.

For a mildly tuned M2 with fresh factory plugs, the stock bosch plugs are totally fine.

For a tuned track junkie? I'd go with NGK's just for peace of mind.. that's about it. Gap around 0.028" is totally fine.

[F87source]

Originally Posted by cookiesowns

The biggest thing people forget to mention is plug reliability. The bosch plugs are known to crack the ceramic ( outer ) under higher heat/combustion loads. Especially on the hot v S63 V8's.

I personally went to 95706 as I intend on running E85 which has a faster flame front in which the colder plug will help with reliability.

For a mildly tuned M2 with fresh factory plugs, the stock bosch plugs are totally fine.

For a tuned track junkie? I'd go with NGK's just for peace of mind.. that's about it. Gap around 0.028" is totally fine.

Well actually the reports of the bosch plug dropping it's ceramic insulator on the m4 was due to excessive misfiring, this occured mostly during the beginning of the s55's life cycle when not much was known about the cars and people gapped down to 0.018 which could have likely caused said misfires. Ever since then those issues are not as commonly heard.

[F87source]

I would also like to add the stock m4 gts runs alot more power than any tuned n55 without a turbo upgrade will ever make without issues.


Also if you run e85 I don't think it would be a good idea to also go down 1 heat range as well, since e85 already burns colder and a colder plug can potentially cause combustion issues or weird idles.

If you're looking for more reliability I'd just go with the ngk plugs (can't remember the number) that is the same heat range as stock, aka the 1 step colder from the n54 plugs.

[F87source]

One more thing, if the crack is on the top insulator (part not on the inside of the cylinder) there are a couple of reasons:

1) If it is far from the base of the plug and looks like hair line cracks, it is likely to be caused by a poor install aka if the plug was dropped, or a wobble extension was not used a thin wall socket causing the plug to be pressed up against the socket interior cracking it.

2) if the cracks are near the base of the plug where it is threaded into the cylinder head it could be because of high cylinder temps, or high cylinder pressures. (This is the least common issue from what I have seen)

Overall from what I have seen the bosch plugs most commonly failed because of the following reasons:

1) Excessive misfiring causing the internal ceramic insulator to drop, this could be because the plug gaps were insanely tight at 0.018" as knowledge was low when the s55 was new. Also tuning was not what it is now.

2) Top insulator was cracked due to the installation of plugs without the wobble extension which I still see today.



Pure addresses it here post 549-551 and one page before with images: https://f80.bimmerpost.com/forums/sh...066417&page=26

[cookiesowns]

Originally Posted by F87source

Well actually the reports of the bosch plug dropping it's ceramic insulator on the m4 was due to excessive misfiring, this occured mostly during the beginning of the s55's life cycle when not much was known about the cars and people gapped down to 0.018 which could have likely caused said misfires. Ever since then those issues are not as commonly heard.

No. BMW uses the same bosch plugs in S63's and S55's. There were issues with the ceramic cracking, these are stock & tune only cars ( no plug gapping )

That said it does not seem nearly as common as they are early on in its life cycle.

Food for thought... M4 GT4 runs the NGK's.

[F87source]

Originally Posted by cookiesowns

No. BMW uses the same bosch plugs in S63's and S55's. There were issues with the ceramic cracking, these are stock & tune only cars ( no plug gapping )

That said it does not seem nearly as common as they are early on in its life cycle.

Food for thought... M4 GT4 runs the NGK's.

That's weird I wonder why it stopped, I haven't found any threads pertaining to that anymore.


The more recent threads I have seen were all attributed to user error, i.e. spark plug tool without wobble extension and too small gap causing misfire.

[cookiesowns]

Originally Posted by F87source

That's weird I wonder why it stopped, I haven't found any threads pertaining to that anymore.


The more recent threads I have seen were all attributed to user error, i.e. spark plug tool without wobble extension and too small gap causing misfire.

Production variances maybe. Yeah I've heard from more than a handful of shops, that said, who knows, there's so many cars out there and only a handful of issues that crop up here and there, tuned or not.

Nonetheless, the NGK's overall just seem more stout anyways.

[F87source]

Originally Posted by cookiesowns

Production variances maybe. Yeah I've heard from more than a handful of shops, that said, who knows, there's so many cars out there and only a handful of issues that crop up here and there, tuned or not.

Nonetheless, the NGK's overall just seem more stout anyways.

Also note that there are 2 bosch part numbers for plugs on the S63, one for the plugs that were discontinued in 2013 and the superceeding part number which is shared on the S55.

So it might have been an issue on the old plugs which is why you don't hear it anymore.

[cookiesowns]

Originally Posted by F87source

Also note that there are 2 bosch part numbers for plugs on the S63, one for the plugs that were discontinued in 2013 and the superceeding part number which is shared on the S55.

So it might have been an issue on the old plugs which is why you don't hear it anymore.

Great find!

[F87source]

Originally Posted by cookiesowns

Great find!

Thanks!

I just did not want to go to a 1 step colder plug unless I had absolutely no choice. Plus for $5/plug for a bosch plug that is a really really good deal, meaning I can frequently swap out plugs.


Ok here is the difference for anyone who cares:

1) RB ZMR5TPP330 or BOSCH ZR5TPP330A (BMW P/N: 12120039634)
FCP URL: https://www.fcpeuro.com/products/bmw...145541#fitment

This is the new updated plug p/n introduced in 07/01/2013, and is found in the m2's n55, m2c/m3/m4, F10 s63, X series M with the S63. I believe this is the updated plug that does not experience the same cracking issue, and any issues that I have seen were attributed to knock or not using a flexible extension on the plug tool.


2) RB ZMR5TPP339 or BOSCH ZR5TPP33 (BMW P/N: 12120038832)
FCP URL: https://www.fcpeuro.com/products/bmw...ch-12120037580

This is the superceded BMW spark plug part number introduced in 09/01/2011 and ended in 06/13/2013. This plug was introduced when the S63 was announced with the debut of the F10 in 2010, I believe this is the plug with the cracking issues as described by cookiesowns

[F87source]

Oh and one more very interesting find:

1) This is a quote from bimmerworld: "Cracks may form on the ceramic insulator of the spark plug. This can cause misfires and rough engine running. This only appears to apply to one batch of plugs for cars made in mid-2009 but BMW was still advising inspection and replacement as late as 2014. If your engine has Bosch ZR5TPP339 spark plugs they should be replaced with the newer design, part # ZR5TPP330A (BMW part #12120040581). BMW had a service action to replace them free of charge. If you have misfires don't overlook the obvious!"

2) This is a link to a bmw recall tsb: https://static.nhtsa.gov/odi/tsbs/20...48022-9999.pdf

Both of them talk about the spark plug cracking and a new bosch part number.

[Sultan hamdi]

Originally Posted by F87source

Here is a spark plug related quote from Justin aka Twisted Tuning whom I personally deem to be the best tuner for this platform - as he owns all the engines he tunes so he experiments on his own cars and not customer cars and thus has no history of blowing engines. He also works with MHD on developing their tuning platform so he knows what he's doing - along with offering custom wmi tuning with the torqbyte hardware.

Anyways that was a bit off topic but here is the quote:

I agree totally , I tried these and the car went puff puff and stuttered all over once I get into load out of the boost and in to the hi timing curve , my car is an M2 f87 OG N55 stage 2 FIC charge pipes and Down-pipe
It was ok but not perfect with just a stage 1 , once I started to ask power from it with the stage 2 the spark went capoot , I will be installing OEM plugs tomorrow, I will bet it will be sorted

[F87source]

Originally Posted by Sultan hamdi

I agree totally , I tried these and the car went puff puff and stuttered all over once I get into load out of the boost and in to the hi timing curve , my car is an M2 f87 OG N55 stage 2 FIC charge pipes and Down-pipe
It was ok but not perfect with just a stage 1 , once I started to ask power from it with the stage 2 the spark went capoot , I will be installing OEM plugs tomorrow, I will bet it will be sorted

Yeah spark plugs that are gapped too tight will cause issues, keep us posted after you install the OEM plugs I'm interested in the results. Hopefully everything will be fixed once you go swap over.

[Sultan hamdi]

So I just received the car from the work shop , and just as u got in I felt ideal was better , then I took it for a drive ambient temperature today is 35.5C did a few small pulls so far so good , now for the main question, why was there miss fire

Here are pics of both old 2016 BMW/M plugs and new one month old Bosch zr5tpp33 plugs

You can see the the BMW showing damage on the ceramic but that is a given as it is 7 years old ,

The big surprise was the Bosch plugs also showing ceramic damage at only one month old ,

As a result I am sure that sticking to the BMW/M is the way to go in plugs until you reach the 700WHP mark

[Sultan hamdi]

Some more pics of the Bosch plugs