Technical BL Coil Investigation and Solution

aus335iguy

Lieutenant
Nov 18, 2017
932
Correct me if I'm wrong but am i reading correctly that these coils are a straight fit on an N54 vs the red top ones that needed alteration?
 

Panzerfaust

Lieutenant
Jul 3, 2018
504
Chicago
Correct me if I'm wrong but am i reading correctly that these coils are a straight fit on an N54 vs the red top ones that needed alteration?
These ones need minor alterations still. But they're significantly easier. You should be able to cut off the metal tip and break the two plastic tabs up top and they'd fit. In my case I had to still strip the coating because it was too late to run out and buy new tools, but they're currently 100% seated.
 

fmorelli

Colonel
Staff member
Aug 11, 2017
2,223
Virginia
Well, a couple things from my experiment.
First off, thank you for posting this, pursuing another option, and being so detailed!
The good news, part A: my coils are clearly seated, you can feel when the rubber grabs onto the plug and there's a nice suction-y "pop!" when pulling them off the plug just like with our OE coils, and my measurements line up with that too (see attached pics)
Just from our experience, we heard positive sounds as well (and so did many others, which is part of why people thought the original coils plugged in). Turns out the sound was the coil pushing into the shrinking and curved shaft. Measurement trumps everything!

The shaft narrows and curves, which is why the width of the coil end matters and why the factor - with a socket we determined the bottom of the shaft was 17.8mm wide. You might double check that the end of your coil is not wider than that.

I'm just giving you my paranoia from when we did all of this ... we got fooled several times along the way. I hope what you find is a good alternative coil! Thanks again for all the research.

Filippo
 

Panzerfaust

Lieutenant
Jul 3, 2018
504
Chicago
First off, thank you for posting this, pursuing another option, and being so detailed!

Just from our experience, we heard positive sounds as well (and so did many others, which is part of why people thought the original coils plugged in). Turns out the sound was the coil pushing into the shrinking and curved shaft. Measurement trumps everything!

The shaft narrows and curves, which is why the width of the coil end matters and why the factor - with a socket we determined the bottom of the shaft was 17.8mm wide. You might double check that the end of your coil is not wider than that.

I'm just giving you my paranoia from when we did all of this ... we got fooled several times along the way. I hope what you find is a good alternative coil! Thanks again for all the research.

Filippo
I actually did measure that too and have pics, just didn't attach them to that post due to being at work. But here's the pics with the metal (I think the width is the *only* thing keeping these ones from fitting with the shielding on actually), one of just the rubber, and then one of how my coils look now as-installed just for shits n gigs, with some comparisons thrown in too.

Even aside from the suction and pops, I could see the dielectric grease pushed back in the opening of the coil after installing and pulling it out. I'm 100% sure my coils are properly seated, and 99% sure they'd fit even with just the shielding on the tip cut back. I took measurements and pictures of everything pre-stripping and installation so if you wanna see anything else let me know!
Snapchat-1017595060.jpg
Snapchat-1220184234.jpg
Snapchat-997576935.jpg
Snapchat-1192849111.jpg
Snapchat-190969686.jpg
 

Attachments

  • Informative
Reactions: fmorelli

Rob09msport

Captain
Oct 28, 2017
1,203
Monroe CT
These coils were one of my favorite mods boy has that changed. At least now they can be considered a true n54 upgrade completely unconventional and we all did it wrong at first lol
 

Panzerfaust

Lieutenant
Jul 3, 2018
504
Chicago
These coils were one of my favorite mods boy has that changed. At least now they can be considered a true n54 upgrade completely unconventional and we all did it wrong at first lol
What do you mean it's changed, you don't like them any more? Personally I'm super happy, the car has never felt smoother and it even feels stronger in that mid to mid-high range.

Regarding doing it wrong for a while at first - hey man, there were years where large amounts of people tried to say a drop-in filter replacement on the stock airbox would outflow any other intake setup... now compare that to what inlets do. Tuners also thought timing retard was the same across all cylinders so only logging cyl 1 was standard for a while. Shit, there's probably stuff even now we have wrong that can be improved on still (I'm thinking PCV setups still but who knows :tearsofjoy:)
 
  • 2Like
Reactions: kayzrx82 and fmorelli

kayzrx82

Corporal
Apr 4, 2018
109
I actually did measure that too and have pics, just didn't attach them to that post due to being at work. But here's the pics with the metal (I think the width is the *only* thing keeping these ones from fitting with the shielding on actually), one of just the rubber, and then one of how my coils look now as-installed just for shits n gigs, with some comparisons thrown in too.

Even aside from the suction and pops, I could see the dielectric grease pushed back in the opening of the coil after installing and pulling it out. I'm 100% sure my coils are properly seated, and 99% sure they'd fit even with just the shielding on the tip cut back. I took measurements and pictures of everything pre-stripping and installation so if you wanna see anything else let me know!View attachment 15553 View attachment 15554 View attachment 15555 View attachment 15556 View attachment 15557

Hey Panzerfaust, How are these fitting compared to the red top ones? Curious how these are.
 

Panzerfaust

Lieutenant
Jul 3, 2018
504
Chicago
Hey Panzerfaust, How are these fitting compared to the red top ones? Curious how these are.
No issues at all so far. I haven't tried the red top ones (OEM or @fmorelli modded) so I can't directly compare, but these ones are 100% seated. Confirmed with my measurements and you can see the dielectric grease pushed back around the plug seat inside the coil.

I did end up removing the little wiring harness bracket too recently, just to literally give me some wiggle room with the coil positioning and so I could route the OE wires more cleanly, but even how I had the coils positioned in my original post they were seated fine.
 
  • Like
Reactions: kayzrx82

Rob09msport

Captain
Oct 28, 2017
1,203
Monroe CT
What do you mean it's changed, you don't like them any more? Personally I'm super happy, the car has never felt smoother and it even feels stronger in that mid to mid-high range.

Regarding doing it wrong for a while at first - hey man, there were years where large amounts of people tried to say a drop-in filter replacement on the stock airbox would outflow any other intake setup... now compare that to what inlets do. Tuners also thought timing retard was the same across all cylinders so only logging cyl 1 was standard for a while. Shit, there's probably stuff even now we have wrong that can be improved on still (I'm thinking PCV setups still but who knows :tearsofjoy:)
I still love end result but I meant as far as my feelings about it. Basically if I bought another n54 I would prob go pr . To me a good mod is one that works as intended when installed as per manufacturer. I have alot of things on my car im happy with but they took tinkering but when i spend 480 for a harness and 100 worth of coils I shouldnt have to modify anything unless I'm not following intended application.
 

Panzerfaust

Lieutenant
Jul 3, 2018
504
Chicago
I still love end result but I meant as far as my feelings about it. Basically if I bought another n54 I would prob go pr . To me a good mod is one that works as intended when installed as per manufacturer. I have alot of things on my car im happy with but they took tinkering but when i spend 480 for a harness and 100 worth of coils I shouldnt have to modify anything unless I'm not following intended application.
Eh, I see where you're coming from to a large extent. But I also feel that once you really dive into the aftermarket - especially past things like intakes and exhaust - you're gonna run into some fitment issues and tinkering at some point.

Should you guys have had to do so much modification and waiting for a new harness? Definitely not. But if you told anyone not from the N54 scene that you were converting your BMW's ignition system to that of a supercar's, they'd probably expect a lot more than some trimming of coils.

I really think the issue would be resolved if BL shipped the kit with the other style of coils and provided some instructions, but that's just me. Maybe I'll try some other smart coils, print a PDF and release my own "2000hp drag car" kit instead lol.
 

JBacon335

Corporal
Nov 7, 2016
147
Brick, NJ
I'm still on my original connectors, was going to modify the coils but they've still been fine besides filing down ever so gently the cylinder 1 adapter plug and I won them on the raffle here. Still on the plugs that had 15k+ on them when I put the coils in. I haven't modded anything just because nothing has gone wrong yet
 

fmorelli

Colonel
Staff member
Aug 11, 2017
2,223
Virginia
Oh I'm aware, just surprised it's been ok for so long. I don't feel the need to play with it if it's working
We had a guy in our stable running a 1M on road courses who didn't have a problem for a while (and road course driving with a Motiv single ... you know it was kicking that ignition system in the ass). One day ... bam ... problem. I'm not surprised all is ok ... that seems to be a common experience for some of the folks, for a period of time at least.

Filippo
 

Torgus

Captain
Nov 6, 2016
1,099
Boston
Oh I'm aware, just surprised it's been ok for so long. I don't feel the need to play with it if it's working
I understand where you are coming from but given how quick it is to fix this and its proven there is a major issue, it seems like a no brainer.

Best of luck.
 
  • Like
Reactions: JBacon335

Panzerfaust

Lieutenant
Jul 3, 2018
504
Chicago
I understand where you are coming from but given how quick it is to fix this and its proven there is a major issue, it seems like a no brainer.

Best of luck.
Yep, same here.

When you do eventually change coils for one reason or another, I recommend using the newer revision ones like I did. Will save you lots of hassle and it (usually) never hurts to be on the newest hardware, as evidenced by our injectors.
 
  • 2Agree
Reactions: Torgus and JBacon335

JBacon335

Corporal
Nov 7, 2016
147
Brick, NJ
so I finally modded my coils and ended up with a couple misfires, changed out a coil on #6 now #3 is misfiring. I should have just left well enough alone
 

veer90

Lieutenant
Nov 16, 2016
897
West Nyack, NY
so I finally modded my coils and ended up with a couple misfires, changed out a coil on #6 now #3 is misfiring. I should have just left well enough alone
Either you got grease on the plug terminals or they're not seated right, plugs old, etc etc.

This is not rocket science, I went the no fucks given route trimmed my coils with a dremel and no issues since. 0.024" gap at 33 psi all day no misfires
 
Top