Spark Plugs

rrfitness20 · 11-19-2021, 08:34 PM

Getting my car tuned soon (:
Any dangers in getting them installed 2 weeks prior to tune ?
NGK .22

rostrata · 11-20-2021, 01:33 AM

Nope. You may see a small decline in mileage but if you're tuning, you won't give a shit either way. What tune are you going with?

rrfitness20 · 11-20-2021, 08:31 AM

Going with MP. I just didn't want the car to misfire or something on a stock tune

Lonmon · 11-20-2021, 10:06 AM

You should be fine either way. I replaced mine with NGK gapped down before tuning and all was good. I didn't notice any notable difference in fuel mileage either. I was still capable of averaging close to 30mpg if driven lightly to and from work. Even after tuned you can get that mileage. Obviously if your foot is in it more mileage will vary. I usually get between 25-28 with mixed style of driving. Tightening up the spark gap just intensifies the spark a little to make sure it doesn't blow out at higher boost levels. It will not be any less likely to fire on a stock tune. Widening the gap can help burn the fuel more completely (mentioned possible fuel mileage increase or more power) however if gapped too much can cause the spark to blow out. With what little we are changing the gap not much is changed except for a little insurance against the aforementioned spark blow out on higher boost when tuned.

rrfitness20 · 11-20-2021, 10:23 AM

Thanks for that Info. As far as gapping them did you go with .22?

Lonmon · 11-21-2021, 09:16 PM

I believe I used Mission Performance's recommendation of .025".

serg1282 · 11-22-2021, 12:02 PM

I gapped and installed mine a few weeks before flashing the MP stage 2 tune. No issues.

chenry · 11-22-2021, 12:13 PM

I went with .22

One time Alex at Mission Performance just regapped my exiting plugs and one time Alex installed a new set for me while I was there (different cars)

OP - if it's easier on you, and you are paying MP a visit, might just want to have Alex slap them in for you (I'm sure he would if you ask ahead of time) while you're there

Just a thought

bimmerboy71195 · 06-04-2022, 06:58 AM

Is there a thread on here on how to replace spark plugs for g20?

BigSky702 · 06-04-2022, 08:33 AM

Quote:

Originally Posted by bimmerboy71195

Is there a thread on here on how to replace spark plugs for g20?

Cool video here … I'm almost brave enough to try it!

bimmerboy71195 · 06-04-2022, 03:02 PM

Quote:

Originally Posted by BigSky702

Quote:

Originally Posted by bimmerboy71195

Is there a thread on here on how to replace spark plugs for g20?

Cool video here … I'm almost brave enough to try it!

That is a good video Iv never tried it doesn't look to hard

JetPump · 06-21-2022, 07:09 AM

Is the NGK 95248 the correct M340i spark plug?

njfoses · 06-21-2022, 07:57 AM

Quote:

Originally Posted by JetPump

Is the NGK 95248 the correct M340i spark plug?

No. Use NGK 94201.

mike@x-ph.com · 06-21-2022, 11:43 AM

Quote:

Originally Posted by JetPump

Is the NGK 95248 the correct M340i spark plug?

Quote:

Originally Posted by njfoses

No. Use NGK 94201.

+1 the 94201 are recommended for the B58

JetPump · 06-21-2022, 07:57 PM

Thanks guys!

ventjock · 04-08-2023, 05:29 PM

Any idea how often should the NGKs get replaced? Just replaced my stock plugs at 36k miles. Running stage 1 MHD.

Thanks!

11-19-2021, 08:34 PM	#1
rrfitness20 Private First Class 77 Rep 138 Posts Drives: Bmw m340i Join Date: Sep 2020 Location: Los Angeles iTrader: (0)	Spark Plugs Getting my car tuned soon (: Any dangers in getting them installed 2 weeks prior to tune ? NGK .22
	Appreciate 0 Tweet Quote

11-20-2021, 01:33 AM	#2
rostrata Second Lieutenant 124 Rep 219 Posts Drives: '20 M340iX Join Date: Mar 2021 Location: Las Cruces, NM iTrader: (0) Garage List 2020 BMW M340i X Drive [0.00]	Nope. You may see a small decline in mileage but if you're tuning, you won't give a shit either way. What tune are you going with?
	Appreciate 0 Quote

11-20-2021, 08:31 AM	#3
rrfitness20 Private First Class 77 Rep 138 Posts Drives: Bmw m340i Join Date: Sep 2020 Location: Los Angeles iTrader: (0)	Going with MP. I just didn't want the car to misfire or something on a stock tune
	Appreciate 0 Quote

11-20-2021, 10:06 AM	#4
Lonmon Private 60 Rep 50 Posts Drives: 2020 BMW M340i x Join Date: Oct 2020 Location: Pa/Md iTrader: (0)	You should be fine either way. I replaced mine with NGK gapped down before tuning and all was good. I didn't notice any notable difference in fuel mileage either. I was still capable of averaging close to 30mpg if driven lightly to and from work. Even after tuned you can get that mileage. Obviously if your foot is in it more mileage will vary. I usually get between 25-28 with mixed style of driving. Tightening up the spark gap just intensifies the spark a little to make sure it doesn't blow out at higher boost levels. It will not be any less likely to fire on a stock tune. Widening the gap can help burn the fuel more completely (mentioned possible fuel mileage increase or more power) however if gapped too much can cause the spark to blow out. With what little we are changing the gap not much is changed except for a little insurance against the aforementioned spark blow out on higher boost when tuned. __________________ 2020 M340i Xdrive Portimao AA catless downpipe (offroad only of course) BMS intake and Inlet tube H&R Springs MHD Stage 2 E40
	Appreciate 3 rrfitness2076.50 MAKH 588.50 Chubbiejones891.00 Quote

11-20-2021, 10:23 AM	#5
rrfitness20 Private First Class 77 Rep 138 Posts Drives: Bmw m340i Join Date: Sep 2020 Location: Los Angeles iTrader: (0)	Thanks for that Info. As far as gapping them did you go with .22?
	Appreciate 0 Quote

11-21-2021, 09:16 PM	#6
Lonmon Private 60 Rep 50 Posts Drives: 2020 BMW M340i x Join Date: Oct 2020 Location: Pa/Md iTrader: (0)	I believe I used Mission Performance's recommendation of .025". __________________ 2020 M340i Xdrive Portimao AA catless downpipe (offroad only of course) BMS intake and Inlet tube H&R Springs MHD Stage 2 E40
	Appreciate 0 Quote

11-22-2021, 12:02 PM	#7
serg1282 First Lieutenant 72 Rep 333 Posts Drives: through Join Date: Jul 2009 Location: NJ iTrader: (0)	I gapped and installed mine a few weeks before flashing the MP stage 2 tune. No issues.
	Appreciate 0 Quote

11-22-2021, 12:13 PM	#8
chenry Colonel 2358 Rep 2,964 Posts Drives: BMWs Join Date: Feb 2012 Location: SoCal Huntington Beach iTrader: (8)	I went with .22 One time Alex at Mission Performance just regapped my exiting plugs and one time Alex installed a new set for me while I was there (different cars) OP - if it's easier on you, and you are paying MP a visit, might just want to have Alex slap them in for you (I'm sure he would if you ask ahead of time) while you're there Just a thought
	Appreciate 0 Quote

06-04-2022, 06:58 AM	#9
bimmerboy71195 Private First Class 68 Rep 115 Posts Drives: alpine white 340xi Join Date: Feb 2018 Location: long island iTrader: (0)	Is there a thread on here on how to replace spark plugs for g20?
	Appreciate 0 Quote

06-21-2022, 07:09 AM	#12
JetPump New Member 2 Rep 17 Posts Drives: BMW M340i RWD Join Date: May 2020 Location: SoCal iTrader: (0)	Is the NGK 95248 the correct M340i spark plug?
	Appreciate 0 Quote

06-21-2022, 07:57 PM	#15
JetPump New Member 2 Rep 17 Posts Drives: BMW M340i RWD Join Date: May 2020 Location: SoCal iTrader: (0)	Thanks guys!
	Appreciate 0 Quote

04-08-2023, 05:29 PM	#16
ventjock Second Lieutenant 65 Rep 244 Posts Drives: 2020 M340i Join Date: Dec 2018 Location: Atlanta iTrader: (0)	Any idea how often should the NGKs get replaced? Just replaced my stock plugs at 36k miles. Running stage 1 MHD. Thanks!
	Appreciate 0 Quote