My COP Conversion
 

Since my car needed new wires, and they are expensive I looked into doing a COP conversion. There are some nice kits, but I like to make stuff myself and save $$.

The info is already out there on how to do it, and it's very easy. The biggest PITA is doing the connector to the factory wiring. I chose to hack the factory coil up to get the connector. Here's some quick and dirty info on my conversion.

I used the info from:
http://www.318ti.org/forum/showthrea...oil+conversion
http://forums.bimmerforums.com/forum....php?t=1103482


I was able to get the coil harness and some used coils from a friend for free (after I had already bought new coils from FCP Groton)

I sourced the hardware from mcmaster.com. Stainless steel, and enough for two conversion, minus the studs.

8975K534 MULTIPURPOSE ALUMINUM (ALLOY 6061), 1/8" THICK X 2-1/2" WIDTH X 3' LENGTH EA $9.10

91292A137 METRIC 18-8 SS SOCKET HEAD CAP SCREW, M6 THREAD, 20MM LENGTH, 1MM PITCH 1PK 1 0 $4.28 PK $4.28

93805A333 METRIC 18-8 SS FULLY THREADED STUD, M6 SIZE, 60MM LENGTH, 1MM PITCH 2 EA 2 0 $1.91 EA $3.82

94920A400 BLACK CLASS 8 STL SERRATED-FLANGE HEX LOCKNUT, M6 SIZE, 1MM PITCH, 10MM WIDTH, 5.5MM O'ALL H 1 PK $7.49

Merchandise Amount: $24.69


The coils I bought were under 25 bucks each NEW from FCP Groton. (I ended up using the used coils.)

You can buy the individual coil connectors and pins from BMW or just get a used harness from ebay, a junkyard, or wherever.

The plate is pretty straightforward to make, especially if you have a spare valve cover sitting around. I placed the plate flat in the valve cover and traced the spark plug holes from the bottom with a sharpie. For the 2 retainer bolts I used a long small screwdriver to scratch the location in the aluminum. I also marked the end of the valve cover to mark what length the plate needed to be.

The main holes for the packs can be cut with a 1 1/2" hole saw and then trimmed to fit.(dremel, die grinder) Once that's done, drop the packs in place and mark where the mounting holes need to be drilled. (NOTE: the #1 cylinder coil pack mounting tab has to be cut) Drill them out and then tap them for the M6 bolts. The studs go in the head, you have to pull the washer and rubber gasket off the 2 valve cover bolts and put them on the studs, the use 2 of the bolts to tighten them down.

Wire it up, toss em on and go.

http://www.318ti.org/forum/attachmen...8&d=1283128668

awesome, I've never heard of this. Notice any increases?

The idle is a bit smoother, and suprisingly highway cruising is much, much smoother and doesn't feel as loaded. The milage has gone up a little bit too. I'm averaging 33 by the OBC, about 1mpg better than before. My wires were original, and in bad shape too.

Never heard of it!? There are a few people here running them, and one member selling kits. http://www.318ti.org/forum/showthread.php?t=31333

I'd like to redo the wiring. It'd be nice if the guy sold the wiring seperate.