[850CSi]

Hey all,

There’s been some discussion on this issue but I’ve never seen straightforward feedback on which way to go.

I ordered a set of new Delphi coils to go with new NGK spark plugs.

I quickly discovered that while the coils themselves seem to fit nicely into the tubes, the connectors on my 8/2005 build 325i have offset tabs.

As far as I know, there are no Delphi coils designed for these early cars and so I have 2 options:

• Stick with Bosch coils
• Trim the notch/slot/tab on the Delphi coils and just use those

Thoughts? How much better are the Delphi coils, really?

[e91Owner]

Originally Posted by 850CSi

Hey all,

There's been some discussion on this issue but I've never seen straightforward feedback on which way to go.

I ordered a set of new Delphi coils to go with new NGK spark plugs.

I quickly discovered that while the coils themselves seem to fit nicely into the tubes, the connectors on my 8/2005 build 325i have offset tabs.

As far as I know, there are no Delphi coils designed for these early cars and so I have 2 options:

• Stick with Bosch coils
• Trim the notch/slot/tab on the Delphi coils and just use those

Thoughts? How much better are the Delphi coils, really?

I've heard that others have cut off the tabs, so I guess you are correct that they are not compatible with the really early build e90s. I haven't had any issues with my BMW genuine Bosch coils (2010/11–still originals).

[lowrydr310]

The Delphi coils are allegedly better, though I'm not exactly sure why. BMW parts switched to Delphi from Bosch at some point.

It's my understanding that there may be some other changes besides the tabs. I read a handful of posts that talked about how the length of the coils were different and may not fit properly. I have a 6/06 build 325 with the newer coils and I replaced them with the exact fit Bosch coils specified. I also have a 12/05 build 330i which uses the older design with the offset pin on the connector, and may need coils within the next year or so. I plan to stick with the correctly specified Bosch coils unless I can confirm 100% that some updated part will fit.

I'm hoping someone with direct experience can comment here and not just a bunch of random people speculating.

[Phil325i]

OP you might find this of interest...

[mehrlovin]

I used new Bosch ones and they've been fine. No complaints. Sometimes I just remove the tab and use a screwdriver to simply remove them if needed. The tabs all stink anyway

[Aqid]

The bosch ones keep failing on my car. I think I went through about 4-5 of them in the last 20k miles. I ended up buying Eldor's from FCP Euro with lifetime warranty. They are installed in the 760i I believe. They work just fine for now, but I just installed them. The real test is going to see how long they'll stay working.

Side note: What is the standard spark plugs that everyone is running now? And what should they be gapped at? I see a lot of NGK. I'm still running the Bosch ones pre-gapped on MHD S2+. Feel that I should probably go a step colder. What's the model number that everyone uses?

[bluewater328]

I think its worth noting to some that, the video that explains the coils doesn't differentiate between engines and the Eldor coils aren't really made (nor needed) for N52. The real progression of coils was something like Bosch, Delphi, Bosch again, then Eldor, IIRC. And Bosch doesnt make the crappy ones anymore, only the retail operation places carry the so-so ones (autozone, Napa, Oreilly, etc). I've run Delphi and Bosch...no real difference in their latest models.