B58 Ignition Coil DIY solutions

wheela

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My comment is also meant as friendly humor, I do like the creativity if that solution. I took a hacksaw to the throttlebody bracket on my old 3g eclipse so I could fit on an EVO 8 fuel rail and FPR :) I even spray painted it with black thermal paint so it would look pretty.
 

rbryant

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Jul 26, 2018
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Haha! I never had one, but heard those dodge daytona guys back in the day would just tighten up the wastegate and let 'er rip! And hope she didn't blow up!
Hehe yea well it was the early days in the 90s... Usually it was a bleed valve that just didn't tell the ECU how much boost was running at first and that blew up a lot of engines...

Then they discovered a grainger valve from the late Gus Mahon and his 13 second minivan.

Lots of mechanical boost controllers were essentially based on that.

Anyway going to far off topic now.

There is almost always a cheaper solution to things. That is capitalism. Getting to the one that works best for a good price is what I was trying to build. I could also use a thinner plate and make it a little cheaper but I like covering the boot lip.

The big washer is pretty similar to what I made and that is fine. Spending time vs money or the fun of your own soln is often what car hobbies are about.

Here is what my thin version looked like in comparison. It was powdercoated and used a stainless standoff and jam nut. It worked but I think the 1/4" thick version is nicer.

20211019_113219.jpg
 

F06gc

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Apr 9, 2021
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The orange wire is #1, white is #3 for the B58 connector. BMW seems pretty consistent with the white wire with tracer and the brown wire but other cars may have Red or Green in place of the orange (red on the N55 cars, Red/Green on the B58, Green on my e70 X5).

I have pigtails available with orange/brown/white already crimped into the B58 connector if you are interested, they are not an easy crimp. They can be crimped directly, I did do it on my personal car but it took more work than splicing in pigtails. I also soldered mine after the crimp because it is hard to make a really good crimp with a hand crimper on this connector. That is why I had the pigtails made.

-Rich
Yea I see what u saying now. I cant push the terminals into the connectors all the way. Not a chance :-(
 

rbryant

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Jul 26, 2018
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Yea I see what u saying now. I cant push the terminals into the connectors all the way. Not a chance :-(
They are a small connector. It is VERY difficult to crimp them on in the engine bay. I got it done but it took 3x longer than I thought it would and was very frustrating.

Either splicing the pigtails in or depinning and swapping the connector for an adapter is the best DIY soln. The custom connectors from vendors are also a great solution but this thread is more focused on DIY. :)
 

GnomeChild

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Sep 14, 2018
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I know this is a massive necrobump but I have to ask...

Did anyone figure out boot options for OEM BMW (Eldor) coils? The OE Eldor coils are slightly different than the BMW branded ones and have a different resistor. I'll be using the BMW branded ones and I haven't seen the resistor for them thrown around very much in the thread besides Rich with his setup

After seeing the clean bracketless install that OP posted, I knew that is exactly how I wanted to install my coils. I have the various connectors and headstuds/bolts + coils sitting in shopping carts waiting for me to run my card but the boot/spring/resistor solution is the missing piece of the puzzle

The boots used in the Nexsys kit got posted earlier and are $5.29 a pop from Summit Racing, but I have no clue if they even come with springs, and there are reports that BMW switched to a different mold for their OEM Coils so I have no clue what to run/fit now boot-wise. Wondering if I should just pony up and order the boots directly from Bahn to ensure I get the proper boots with springs included and just stuff my B58 resistors inside as well as modify the spring

This is probably more trouble than it's worth and is only saving me a few bucks over the legit bracketed installs but the bracketless install is too clean to pass up :)


EDIT
So it turns out I was able to further source the SPP170E boot from Rock Auto for even cheaper than the Summit Racing link ($3.09 each). The advantage to the Rock Auto link (besides price of course) is that they indeed specify that a spring coil is included. It comes out to about $31 shipped for a set of 6 which is already cheaper by a few bucks than the Summit Racing link that didn't even take tax and shipping into account (even comes without extended 1 month "special order" lead times). I may just pull the trigger and figure it out when I have everything in hand.

I wonder if the Nexsys kit sources custom springs or if they just use the provided Dodge Dart springs and call it a day


EDIT2
Order the SPP223E from rockauto
This one? https://www.rockauto.com/en/parts/s...,SPP223E,spark+plug+/+coil-on-plug+boot,10150

Which coil do you recommend. And did you ultimately find any plate mount that worked wel
For anyone wandering into this thread late to the party and wanting to do the DIY B58 Coils after all the initial hype has died down (like me) I went with these boots for my Coils. I decided to stick to the tried-and-true method instead of venturing into regions unknown. Rock Auto had them in black (not white as pictured by the OP) at $3.20 a piece but came out cheaper overall ($28 shipped) because for some reason shipping was cheaper on these
 
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GnomeChild

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I have finally received the boots and coils from RockAuto/FCP and there is some bad news

There are reports that BMW has changed the design of the flange on the B58 coils to be longer and skinnier; there are reports that this is without a revision or change in part number from BMW. Unfortunately the rubber boots listed above do not fit the coils. I bought brand new OEM Coils that specify Eldor and "BMW" on the top.

9B17C40B-19E3-40C5-BB15-5ABA7736A521.jpeg


You can source older coils with the older flange used but if you would ever need to replace a coil you would be screwed.

42853B35-5094-4946-B72C-0A40DDD347BA.jpeg


Also this rubber boot is beyond a tight fit for the B58 plugs. Whereas the B58 coil fits snug on B58 plugs, the above mentioned boot is tight as can be. This was the furthest I managed to wedge it on before I became uncomfortable with how much effort I was exerting to fit the coil

Also the provided spring? Didn't look like it would work. The boot "passage" is very skinny and looks like it would barely fit the skinny spring, let alone the B58 Resistor

Unfortunately it means I have to return these and take a gamble on the Nexsys style boots I posted earlier. Hopefully they will be a better fit. To add insult to injury, FCP sent me "Champion" branded Spark Plugs when I paid $10 a plug extra for OEM Genuine BMW plugs. Hopefully they won't make a fuss on the return but considering their recent change in return/warranty policy, I have a feeling I will be in for some headache.

Today has not been the best day 😐


EDIT
Here are some more pictures of the new coils I received from FCP

93D2E5D5-5234-4045-8F98-1B8350127578.jpeg


2D5DFF4B-0BB2-4D46-9503-6CE3A398112D.jpeg


C63FCF56-9076-4B94-B65B-88E39AEC5D1C.jpeg


It would make sense why BMW did not change part numbers despite the difference in parts, since the coil and boot are sold together and have the same physical dimensions together as the older coils. I don't think BMW ever had any intentions for anyone to separate them and notice that there is a difference. I'd like to believe that this was just a simple revision but it isn't completely unheard of for BMW to modify their parts just to spite owners of older models or people looking to "futurefit" their older models with new tech/parts

So that's $15 down the drain in shipping charges and if the "Nexsys" style SPP170E boots don't work out that's another $15 gone in returns. At that point it would have just been easier and just as cost effective to buy the boots directly from Nexsys ($60 with their updated springs) but I guess my monetary loss is your informational gain. You will be able to find out which boots/springs fit and you will like it!

YES, YOU! Reading the first page of this topic! You better get your ass over here and read this post because it's important and I'm wasting good money figuring this out so you won't have to! 😝
 
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GnomeChild

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My connectors for the B58 coils also came in from China today. They are composed of a bunch of small and fragile looking/feeling parts but they were a perfect fit and came with all the pins/grommets I needed for 6 coils

B21CCC8C-1D38-4A6F-B2BD-386991E3F8F3.jpeg


475954F1-6965-4F0C-8221-DE1267CFCAD1.jpeg


6612C7D6-F33B-4D6E-992D-2EF59061AF30.jpeg


I think they are the same connectors that Rich uses in his Fat Bunny bracket kit.

I bought them here

I opted not to use the connectors posted earlier in this thread considering they are somewhat bulky and ugly looking + need to be shaved down a little to be made to fit. These connectors fit perfect right out of the box and should work great. I have heard reports that the pins are very hard to insert once completed with wiring so we shall see when I have my extra N54 harness in hand ready to mod

Be extra careful with them if you decide to go with these as they do feel a little fragile (mainly the purple locking connector for the pins)
 

GnomeChild

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Finally, some good news for once. The SPP170E Nexsys boots came in and they looked promising

DC41D22E-FD27-41C9-B90A-7A86B8E3F55C.jpeg
07735966-7D12-451A-A9B4-20927DEF5ADC.jpeg


Nice and deep

AF1A5409-DFCD-496C-8583-0C770E1043AC.jpeg
EB82F8CA-E30E-41A2-AA84-FA4789B66D0D.jpeg


They fit right up to the new style coils. These were the boots I originally wanted to run, so I really should have stuck with my gut here and ordered them first. The only downside is that the provided spring is already preinserted into the boot, so I will have to find a way to remove it without damaging the boot and then adapt the B58 resistor into the setup and figure out how to modify the springs to fit while making good contact with the coil electrode and B58 sparkplugs. The B58 resistor/spring should be long/skinny enough to fit into the B58 Flange and make contact with with electrode so I will probably keep the upper portion of the spring after the resistor mostly stock, but looking for a solution to the spring issue will have to come at another time. Right now I only had time to confirm if the boots fit, to which I can say; yes, yes they do 😃

It would have been obvious to everyone, considering these are the Nexsys boots; but doubts always arise until you test it for yourself
 
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k4i53r

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Finally, some good news for once. The SPP170E Nexsys boots came in and they looked promising

View attachment 79473View attachment 79474

Nice and deep

View attachment 79475View attachment 79476

They fit right up to the new style coils. These were the boots I originally wanted to run, so I really should have stuck with my gut here and ordered them first. The only downside is that the provided spring is already preinserted into the boot, so I will have to find a way to remove it without damaging the boot and then adapt the B58 resistor into the setup and figure out how to modify the springs to fit while making good contact with the coil electrode and B58 sparkplugs. The B58 resistor/spring should be long/skinny enough to fit into the B58 Flange and make contact with with electrode so I will probably keep the upper portion of the spring after the resistor mostly stock, but looking for a solution to the spring issue will have to come at another time. Right now I only had time to confirm if the boots fit, to which I can say; yes, yes they do 😃

It would have been obvious to everyone, considering these are the Nexsys boots; but doubts always arise until you test it for yourself
Did you figured it out how to fit the original resistor form b58 ?
 

GnomeChild

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Did you figured it out how to fit the original resistor form b58 ?
No, unfortunately juggling 10+ mods at a time, 60-hour mandatory overtime work weeks, and rotating on-call weekends will eat up your freetime. Who would have thought :)

I will eventually get back around to this but not anytime soon; it's low priority. However, it shouldn't be too hard for a motivated individual to figure it out from here. I'd say maybe 70% or so of the legwork is done at this point between mine and previous members efforts, it's just fitting the parts and the buttoning-up the minor details that's left

You're more than welcome to attempt to trailblaze from where I've left off but I also understand the reservation. Sorry I haven't been able to be more of a resource at this time
 
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syn909

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No, unfortunately juggling 10+ mods at a time, 60-hour mandatory overtime work weeks, and rotating on-call weekends will eat up your freetime. Who would have thought :)

I will eventually get back around to this but not anytime soon; it's low priority. However, it shouldn't be too hard for a motivated individual to figure it out from here. I'd say maybe 70% or so of the legwork is done at this point between mine and previous members efforts, it's just fitting the parts and the buttoning-up the minor details that's left

You're more than welcome to attempt to trailblaze from where I've left off but I also understand the reservation. Sorry I haven't been able to be more of a resource at this time

Any new updates on your progress? Also thanks for the documentation!