[Issa.M]

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

[435gc]

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.

[johnung]

Originally Posted by Issa.M

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

[Issa.M]

Originally Posted by johnung

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

[thejeremyman9]

Originally Posted by Issa.M

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.

[johnung]

Originally Posted by Issa.M

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