Outboard Motor Coils

[John G. Napoli]

At 07:59 PM 4/11/96 GMT, diy_efi at coulomb.eng.ohio-state.edu wrote:
>> Question 1:  Would these coils (and, possibly, their electronic controller)
>> have applicability in an automotive application?
>> 
>> This engine also uses unusual spark plugs.  There are no conventional
>> electrodes.  Looking end-on to the plug, it looks like an archery target --
>> three annular rings.  The center ring is the center electrode, the second
>> ring is the insulator, and the third ring is the outer electrode (case).
>> Viewed from the side, the plug is flat across, with the insulating ring
>> slightly recessed.  The spark occurs at any point across the faces of the
>> center and outer rings.  These plugs last a long time, and, of course, there
>> is no gap to adjust.
>
>
>You know I always wondered why they didn't make plugs like that? I see a 
>circular electrode as being nearly foul free, hanving a good spark as the
fround
>expands towards the piston and not at the cylinder walls as with a normal plug.
>
>The questions...
>  1. How far do these suckers stick below the head?

Not far at all.  I would say flush to the head or at most slightly proud.

>  2. How much volatge is used to drive the puppies?

Unknown.  Whatever the coils referenced in the first part of my original
message can put out.  

>  3. How large are they?
>

Look like a regular plug.  13/16" socket.  A friend with a nitrous drag car
grabbed some off my shelf a year ago, wanting to experiment.  But he melted
a piston before he could and the car is not back together yet. 

>              Jim Staff
>              Always looking for a cool way to improve a 3HP Briggs
performance.
>

Use it to drive the alternator on a big block.  (G)  Why not hack an
overhead valve head out of aluminum?





Regards,

John