1997 318ti N54 Coil on Plug Conversion
 

So I performed this modification a few months ago, more out of necessity because I didn't have money at the time for new spark plug wires and had a n54 turbo engine with spun rod bearings taking up space next to my stall that no one wanted... anyhow,

Based on this guys DIY

http://www.r3vlimited.com/board/showthread.php?t=239104

Things needed,

Valve Cover: I grabbed a spare one from a local Pick n Pull
E46-92 wire harness for spark plug coils
4 ignition coils- any ignition coils from m54 all the way to n54 can be used, I used n54

this mod really cleans up the passenger side of the engine bay, as there is no longer a need for the coil pack, plus a coil pack is $160, Plug wires are $200

What happened in my case was I had recently purchased the vehicle and did not know it was running what looked to be the original spark plugs, one of the plugs cracked and burnt a spark plug wire, which meant even after replacing the plug i still had a miss in the engine.

With this modification a replacement coil is about $35 from the dealership.

I'm currently trying to piece together a supercharger kit, and have a feeling that this would be something that could only help with ignition.

This is a pretty simple mod to do as the engine already uses a regular coil pack, so using a wiring diagram cut the wires right before the connector for the coil pack, and splice each wire per plug, the ground wire is the same for all 4 plugs.

the coils are slightly wider than the factory plugs, all you have to do is grind out the valve cover just enough for each coil to squeeze through,

This takes minimal modification and I have been nothing but pleased with the results, I have been running this set up for 8 months now, and have yet to have a problem, and always keep a spare coil in the trunk as I am running used coils with about 50k on them when I got them

any questions, let me know