Hi Lenny,
Just found this thread (devil, idle hands, etc.
) and, without wishing to denigrate the other posters (several of whom I recognise from other Triumph forums), 'fraid you haven't been given correct information.
I have reached out to boyer formation they sent me a list I know it's an MK3 boyer box
Someone's misunderstood you; Boyer-Bransden "red box" is specifically MicroDigital. Bransden colour-codes his boxes, "MK3" is - literally - a black 'box';
his other one is MicroPower, which is a blue 'box'.
Btw, if the bike doesn't have them already, MicroDigital requires either resistor plugs or caps.
do i power and ground each coil independently (parallel) or do i use one power lead in then loop it to second coil and ground out (series)
Never, ever connect multiple coils in "parallel" to a B-B (or Pazon, Tri-Spark "Classic Twin", etc.).
As a general rule, the primary design criterion of coils to be switched by points or points-replacement e.i. is they draw between 3 and 4 Amps when the rated Volts are applied across them; this generally applies to all makes. If you know Ohm's Law (E=IR aka Volts = Amps x Ohms), for a '12V' coil to draw between 3 and 4 Amps, its primary resistance will be between 4 Ohms and 3 Ohms respectively; for a '6V' coil to draw between 3 and 4 Amps, its primary resistance will be between 2 Ohms and 1.5 Ohms respectively, etc.
When two or more electrical components are connected to the same switch in "parallel", their
Amps are added together. This applies whether you're calculating the Amps passing through, say, the ignition switch (ignition + lights + horn + yadda, yadda) or two ignition coils switched by an electronic ignition.
Two '12V' coils connected in parallel to a B-B MicroDigital e.i. will draw between 6 and 8 Amps.
http://www.boyerbransden.com/pdf/KIT00081.pdf are the B-B fitting instructions for a MicroDigital on a Triumph twin; they specifically say, "The maximum ignition coil current through the unit must not exceed 5 amps", so between 6 and 8 Amps
will fcuk (a technical term) the e.i. 'box'.
Connecting multiple coils to a B-B e.i., they must be in "series" - the box is connected to just one coil terminal - "neg" on a "positive earth" bike - that coil's "pos" terminal is connected to the next coil's "neg" terminal, and so on 'til just the last coil in the series "pos" terminal is connected to battery "pos".
Electrical components in "series", their individual
Ohms (resistances) are added together. Problem with that is, when you add the 3-4 Ohms each of two '12V' coils together, you end up with between 6 and 8 Ohms; nominal 12V electrical system and Ohm's Law says the current draw is cut to between 2 and 1.5 Amps respectively. Cutting current draw is good? Not for an ignition coil - they turn input into output and, if you cut the input by half, you cut the output to a quarter; i.e. a coil that could generate 20,000V HT can't generate more than about 5,000V.
Bransden allege you can use two '12V' coils connected in series on a twin; however, ime if you contact them about an ignition problem, one of the first questions they ask is, "Are you using 12V coils?"; if you answer yes, they'll advise you fit 6V coils ...
Your next problem will likely be finding dual-output coils specifically with a primary resistance between 1.5 and 2 Ohms ... Fwiw, years ago, one of the Jap bike makers (Kawasaki?) used 'em for a while in normal 12V electrics, in conjunction with a ballast resistor each. God knows why because, if either coil or b.r. failed, it took out the other component; naturally, of course, neither were cheap to replace ...
Fwiw, most people I know with dual-plugged heads use either B-B MicroPower (blue 'box') or - more preferably - Pazon Smart-Fire. These work more like modern ignitions, in that the coils are special low-resistance (0.5 Ohm?) and are charged by a short (micro-seconds) burst of high Volts (400V?).
do i cross the plug wires over, meaning coil one 14mm plug to cyclinder 1 do i take coil one 10mm waste spark to cylinder 2
Not important whether it's "waste spark" or not.
The important thing with any twin-lead coil is the HT circuit is entirely independent and self-contained (unlike a single-lead coil). As such, the HT Volts are across the plug gaps of both the attached plugs, sparks jump plug gaps in compressed fuel/air worse than they do in uncompressed, so certainly Bransden's advice is each twin-lead coil should be connected to different cylinders. That said, certainly the coils he supplies with MicroPower can generate up to 35,000V and I know people racing high-compression six-plug triples with each twin-lead coil connected to one cylinder.
to add to the mess its pos earth.
Don't get too hung-up on "earth"/"ground". All it means is the structure of the bike is attached to battery "pos". DC electrics work
exactly the same whether the bike's attached to battery "pos" or battery "neg".
In the case of the (any) e.i. 'box', they have one wire for connecting to battery "pos" and another for connecting to battery "neg" (Red and White respectively on B-B and Pazon), one or other through the bike's switches; no e.i. box "earths" through its mounting. Btw, on your bike, for long-term reliability, the e.i. box Red wire and the "pos" wire from the last coil in the "series" should both be connected to battery "pos", not to some other bit of bike.
