The M60 and M62 V8s use eight Bosch Coil-On-Plug (COPs) to fire the plugs :

These are fired sequentially from the original Bosch DME ECU. As far as I'm aware they don't have built in ignitors (the 3rd wire is a shunt circuit to monitor the ignition event).

For aftermarket programmable ECUs, DTA and Motec both produce systems with 8 power ignition channels but they aren't cheap. For budget ECUs it's hard to find an affordable one that will run all eight coils directly, and this was the dilemma i had. Generally the more expensive the ECU is, the more coils it can drive directly.

Megasquirt MS3X with it's expansion board can provide 8 logic ignition outputs, this would need an ignitor box with 8x BIP373 or similar to drive the original COPs. Or instead you could switch something like GM LS1/2 coils which have inbuilt ignitors.

Cheaper aftermarket ECUs only have 2 or 4 ignition channels, so if you go down this route the COPs will need replacing with coil-packs for a wasted spark system, allowing all eight spark plugs to be driven by four ignition drivers.

I used a pair of mid-90s Ford Escort coilpacks  fitted on brackets at the back of the engine bay.

 

MS2 and Microsquirt V2 can be modified to give 4 logic level spark outputs but require external drivers to provide the 12v current to the coils. Instead of fiddling around with this i used an Ford EDIS-8 ignition module to give the 4 outputs for wasted spark coils.

There are several different ignition modules of this type for four and six cylinder cars (Bosch 211, GM DIS, and the Ford EDIS). But the only commonly available 8 cylinder ignition module is the Ford EDIS-8 system, used on various yank-tanks for many years. They're sometimes available on www.Trigger-Wheels.com or they can be picked up on Ebay from the States. The wiring diagrams for these are quite simple and are on the Megasquirt website.


EDIS-8 ignition module:

 And the wiring is fairly straightforward:

 The only hitch with them is that being Ford, they require a 36-1 trigger wheel (36 teeth, 1 missing) whereas the BMW uses a 60-2 trigger wheel.  Which means machining-off the the BMW wheel, and carefully welding on a new 36-1 wheel. These are also available from trigger-wheels.com in various sizes. 

I kept the original BMW crank sensor but moved it to a new position to suit the smaller diameter of the new trigger wheel. If you were driving the coilpacks direct from an ECU with 4 ignition outputs then you could avoid all this and retain the BMW's 60-2 trigger wheel.

Universal 36-1 trigger wheel was just large enough to go over the rear of the pulley diameter when machined  (i can't remember if this was the 6.5" or the 7.25" outer diameter without measuring it again) :

New 36-1 trigger wheel machined to fit the crank pulley :

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