F30POST
F30POST
2012-2015 BMW 3-Series and 4-Series Forum
BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read
BMW 3-Series and 4-Series Forum (F30 / F32) | F30POST > 2012-2019 BMW 3 and 4-Series Forums > General F30 Sedan / F32 Coupe / F36 Gran Coupe Forum > N55 spark plug gapping for future tune
proTUNING Freaks
Post Reply
 
Thread Tools Search this Thread
      02-23-2021, 05:12 PM   #1
Issa.M
New Member
2
Rep
15
Posts

Drives: BMW 335i xdrive (F30)
Join Date: Feb 2021
Location: North Jersey

iTrader: (0)

N55 spark plug gapping for future tune

The time has come to change my spark plugs and I am looking to add bootmod3 stage 1 on my f30 335i xdrive in the near future, maybe 5k miles. I ordered the NGK SILZKBR8D8S (97506) and bootmod3 recommends to gap them to around .023". Will it be fine if I gap them to that spec with no tune or will it cause a rough idle? Let me know your thoughts and experience. Thanks
Appreciate 0
      02-23-2021, 05:39 PM   #2
435gc
First Lieutenant
435gc's Avatar
129
Rep
363
Posts

Drives: 2015 435i Gran Coupe xdrive
Join Date: May 2019
Location: Charlotte

iTrader: (0)

I would start with the stock gap especially for stage 1. Narrow gap is really for higher boost applications.

I would paruse the technical forum for your engine to hear more on spark plugs and gap. Lots of discussion on this topic there.

Last edited by 435gc; 02-23-2021 at 05:51 PM..
Appreciate 0
      02-23-2021, 07:36 PM   #3
johnung
Colonel
United_States
2157
Rep
2,886
Posts

Drives: 2015 BMW 335i x-Drive Auto
Join Date: Oct 2017
Location: New Jersey

iTrader: (0)

Garage List
Quote:
Originally Posted by Issa.M View Post
The time has come to change my spark plugs and I am looking to add bootmod3 stage 1 on my f30 335i xdrive in the near future, maybe 5k miles. I ordered the NGK SILZKBR8D8S (97506) and bootmod3 recommends to gap them to around .023". Will it be fine if I gap them to that spec with no tune or will it cause a rough idle? Let me know your thoughts and experience. Thanks
A Stage1 tune is by definition used with stock hardware. Use stock plugs at stock gap. The BMW engineers choose them to run perfectly. No so called plug upgrade can make your engine run better, but with a plug model/gap change your engine running worse is a big possibility.

The only reason to go to a colder plug with a shorter gap is if you are running very high boost pressures from a Stage2 or higher tune. With so much extra fuel/air density inside the engine cylinder, the spark can have difficulty jumping the longer stock gap.

Here's a link to stock plugs that come gapped to stock gap right out of the box.

https://www.fcpeuro.com/products/bmw...ch-12120037580
Appreciate 0
      02-23-2021, 08:02 PM   #4
Issa.M
New Member
2
Rep
15
Posts

Drives: BMW 335i xdrive (F30)
Join Date: Feb 2021
Location: North Jersey

iTrader: (0)

Quote:
Originally Posted by johnung View Post
A Stage1 tune is by definition used with stock hardware. Use stock plugs at stock gap. The BMW engineers choose them to run perfectly. No so called plug upgrade can make your engine run better, but with a plug model/gap change your engine running worse is a big possibility.

The only reason to go to a colder plug with a shorter gap is if you are running very high boost pressures from a Stage2 or higher tune. With so much extra fuel/air density inside the engine cylinder, the spark can have difficulty jumping the longer stock gap.

Here's a link to stock plugs that come gapped to stock gap right out of the box.

https://www.fcpeuro.com/products/bmw...ch-12120037580
Thank you for the response. Do you think that I can still run the NGK SILZKBR8D8S (97506) gapped to BMW's recommendations?


This is what Pro Tuning Freaks said:
https://bootmod3.atlassian.net/wiki/...+and+which+gap
Appreciate 0
      02-23-2021, 09:35 PM   #5
thejeremyman9
Brigadier General
thejeremyman9's Avatar
2332
Rep
4,586
Posts

Drives: 2015 BMW 335i
Join Date: May 2019
Location: Cali

iTrader: (0)

Quote:
Originally Posted by Issa.M View Post
The time has come to change my spark plugs and I am looking to add bootmod3 stage 1 on my f30 335i xdrive in the near future, maybe 5k miles. I ordered the NGK SILZKBR8D8S (97506) and bootmod3 recommends to gap them to around .023". Will it be fine if I gap them to that spec with no tune or will it cause a rough idle? Let me know your thoughts and experience. Thanks
Don't fall into the colder plugs smaller gap trap. Stock plugs stock gap. Read more here if you want to DIY: https://f30.bimmerpost.com/forums/sh....php?t=1709198

You want the largest gap possible without having misfires. Stock plugs stock gap are proven to work for any stock turbo application, and many push even further with PS2, meth, Emixes, etc. The best approach is to do stock plugs stock gap unless you have problems, then change.
Appreciate 1
Issa.M1.50
      02-23-2021, 11:11 PM   #6
johnung
Colonel
United_States
2157
Rep
2,886
Posts

Drives: 2015 BMW 335i x-Drive Auto
Join Date: Oct 2017
Location: New Jersey

iTrader: (0)

Garage List
Quote:
Originally Posted by Issa.M View Post
Quote:
Originally Posted by johnung View Post
A Stage1 tune is by definition used with stock hardware. Use stock plugs at stock gap. The BMW engineers choose them to run perfectly. No so called plug upgrade can make your engine run better, but with a plug model/gap change your engine running worse is a big possibility.

The only reason to go to a colder plug with a shorter gap is if you are running very high boost pressures from a Stage2 or higher tune. With so much extra fuel/air density inside the engine cylinder, the spark can have difficulty jumping the longer stock gap.

Here's a link to stock plugs that come gapped to stock gap right out of the box.

https://www.fcpeuro.com/products/bmw...ch-12120037580
Thank you for the response. Do you think that I can still run the NGK SILZKBR8D8S (97506) gapped to BMW's recommendations?


This is what Pro Tuning Freaks said:
https://bootmod3.atlassian.net/wiki/...+and+which+gap
The link won't open but I'm assuming that is the posting where they say that they recommend NGK 97506 gapped to 0.022" for tuned cars.
They neglected to say for Stage2 and above tuned cars. Because Stage1 by default means everything is stock.

You may get away with the 97506 that you bought but at $9 per plug I'd just put in stock Bosch plugs and save or sell the others. The 97506 can't improve on the stock plugs on a Stage1 tune, and they might make the engine run less than ideal
Appreciate 1
Issa.M1.50
Post Reply

Bookmarks

Tags
335, bmw, bootmod3, f30, n55, spark plug change, spark plug gapping, tune

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -5. The time now is 07:25 PM.




f30post
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST