Re(2): Q: dual ended ignition coil

[Steven Buchholz]

> use a standard coil and make a Y splitter using some some glass epoxy 
> board and some sutible studs and  insulate the thing with silicon 
> rubber    all the dual coil is in my estimation is an standard hei coil
> with two outputs in parellel    " there's a schematic in my buicks 
> chilton"
> 
... apologies if I am misunderstanding something, but the suggested solu-
tion does not solve the problem as elegantly as the ungrounded coil.  With 
the dual wire coil the spark plugs are in series, meaning that both must 
fire.  Using a Y approach places the plugs in parallel, which does not 
guarantee that both fire.  You might be able to work something by isolating 
the ground on a standard coil, but having the case of the coil at some 
potential other than ground would probably lead to a lot of EMI problems ...

Steve Buchholz
s_buchho at kla.com
San Jose, CA (USA)