Conned I think

Bought a Bosch GT40 ignition coil 'bout a year back. Being heavily involved
with electronics I thought I,d check the thing out against a standard 12
volt coil to see what they altered.
Somewhat surprised I found the primary ( 12 volt side) and the secondary (
ouch side) to have all but identical resistances and inductance. I would
have expected to find lower impedances on the primary at least. I very much
suspect the biggest change here is the colour of the sticker!.
John

On Feb 26, 11:50*pm, "John" > wrote:
>... I found the primary ( 12 volt side) and the secondary (
> ouch side) to have all but identical resistances and inductance....
> I very much
> suspect the biggest change here is the colour of the sticker!.
>------------------------------------------------------------------------

Dear John (and the Newsgroup),

The amount of energy you can use in your ignition circuit is
determined by the amount of energy the swtich can handle. If you need
more energy you would need LARGER POINTS to carry it.

I explained this in 1994, shortly after I began posting VW-specific
messages to the internet. But with the VW magazines insisting a blue
coil was 'hotter," any attempt to inject a whiff of reality was
brushed aside.

-Bob Hoover

Bob,
Spot on. Should also mention the current drain /current rise times of
GT40 "in circuit" was also almost exactly the same as the standard coil..
Same energy in = same energy out. I suspect if the primary was designed to
take more current to give you the higher energy output a firm like Bosch
would have recommended a transistor assisted ignition to avoid having
ignition points burning out every couple of months. Wonderful thing placebo
effect ,eh.
Hope everything is going as well as it can with yourself.
John