[TheHunterHofman]

Hi all,

Can I hear your thoughts on changing the spark plugs on my M2?

So, my M2 currently is 4 years old and has done 15k kilometers (9k miles). Would it be a good time to have the spark plugs changed, and if so, which ones should I get?

Having said that, the car has the following upgraded parts:

1. CSF intercooler
2. FTP chargepipe
3. FTP boostpipe
4. MST turbo inlet pipe
5. MST cold air intake

The software and downpipe of the car are stock.

Again, happy to hear your thoughts on changing out the spark plugs.

Thanks!

HunterHofman

[detroitm2]

I'd say unless you have a specific reason to think the spark plugs need to be replaced, I wouldn't bother. I believe they aren't due for replacement until 30K miles. Maybe a bit sooner for a tuned car.

[VisualEcho]

15,000 miles at a minimum, and as stated, more like 30K normally.

[tux2005]

BMW Canada's service interval I guess was 50,000KM or 3 years for the spark plugs, they were changed for me at the 3 year mark when I took it in for the oil and filter changes (that was despite being at around 30,000KM).

[F87source]

I would go with the stock bosch plugs and stock gap, no need to go to a colder plug unless you are making crazy power (Gtr's use the same heat range plugs as the stock ones and they're fine up to 700 whp) so keep an eye on your plugs to see if they are running too hot and if you need to go colder but chances are you won't need to. Stock gap should be fine up to 450 whp or more (m4 gts and m2cs are running the same plug and gap as us and they're making around this power level without issue). If you notice a misfire then you can start to gap down.


So don't start gapping down for no reason because it can induce harsh idles and stutters.

[TheHunterHofman]

Originally Posted by F87source

I would go with the stock bosch plugs and stock gap, no need to go to a colder plug unless you are making crazy power (Gtr's use the same heat range plugs as the stock ones and they're fine up to 700 whp) so keep an eye on your plugs to see if they are running too hot and if you need to go colder but chances are you won't need to. Stock gap should be fine up to 450 whp or more (m4 gts and m2cs are running the same plug and gap as us and they're making around this power level without issue). If you notice a misfire then you can start to gap down.


So don't start gapping down for no reason because it can induce harsh idles and stutters.

Thanks for your reply. So getting colder plugs wouldn't hurt/negatively affect anything right? Although unnecessary: if it can't hurt, then might as well right?

[TheHunterHofman]

Originally Posted by tux2005

BMW Canada's service interval I guess was 50,000KM or 3 years for the spark plugs, they were changed for me at the 3 year mark when I took it in for the oil and filter changes (that was despite being at around 30,000KM).

Thanks for this. The plugs of my 4 year old M2 have never been replaced, so I'll look into replacing them (mostly for the fun/learning of it).

[F87source]

Originally Posted by HunterHofman

Thanks for your reply. So getting colder plugs wouldn't hurt/negatively affect anything right? Although unnecessary: if it can't hurt, then might as well right?

Hurt no, but possibly cause a rough idle due to incomplete combustion maybe. But the good thing is that these cars aren't super sensitive to plug heat ranges from what I see (they're more gap sensitive). So if you must you can get colder plugs just keep stock gap and don't just gap to 0.020", gap down sparingly and only if needed (stock gap should be absolutely fine even on stage 2+ maps, but if it's not go down in small incriments).

Although keep in mind I think it's a huge waste of money to go with a colder plug for no reason because ngks are $20/plug and the oem Bosch plugs are $6/plug. So over 3x more for no gains or benefits at all (untill you're making significant power).

[PackPride85]

Running a colder plug without the added heat from more power will just foul the plugs faster. No difference in performance though.

[TheHunterHofman]

Originally Posted by F87source

Hurt no, but possibly cause a rough idle due to incomplete combustion maybe. But the good thing is that these cars aren't super sensitive to plug heat ranges from what I see (they're more gap sensitive). So if you must you can get colder plugs just keep stock gap and don't just gap to 0.020", gap down sparingly and only if needed (stock gap should be absolutely fine even on stage 2+ maps, but if it's not go down in small incriments).

Although keep in mind I think it's a huge waste of money to go with a colder plug for no reason because ngks are $20/plug and the oem Bosch plugs are $6/plug. So over 3x more for no gains or benefits at all (untill you're making significant power).

Duly noted, thank you. Makes more sense to go with OEM plugs then.

[TheHunterHofman]

Originally Posted by PackPride85

Running a colder plug without the added heat from more power will just foul the plugs faster. No difference in performance though.

Got it, thanks

[F87source]

Originally Posted by HunterHofman

Duly noted, thank you. Makes more sense to go with OEM plugs then.

Yup.

[bluescoupe]

What is the OEM Bosch plug for the OG M2, N55?
I've seen all ranges of part numbers and prices.

[Duke Silver]

Originally Posted by bluescoupe

What is the OEM Bosch plug for the OG M2, N55?
I've seen all ranges of part numbers and prices.

BOSCH-ZR5TPP330 is the Bosch plug that I used on my OG and is apparently the OE spark plug. When I priced them in Australia they were 1/3 the cost of the oem spark plug from the dealership.