Conned I think

Bought a "run out" special of a Bosch GT40 coil from local supermarket 'bout
a year ago. Being involved heavily with electronics I thought I,d check the
thing out against a standard coil to see what they changed. Somewhat
surprised I found the primary ( 12 volt side) and the secondary ( ouch side)
to have almost identical resistances/inductance to a standard coil!. To have
more secondary voltage you either need less turns on the primary or more on
the secondary (or both). I,ve got a suspicion the only difference here is
the colour of the "sticker".
John

 

Sorry, meant this for a VW group.
John

 

Unless of course the wire size or core is different.

Jeff

 

Measuring the coil ohms has nothing to do with the power it can provide.

The only way you're going to know if something has changed is if you
install it and measure the output, the current draw (load), etc... There
are several variables you can't measure with an ohm meter.

 

Too right, as previous correspondent mentioned resistance could be the same
but having more turns of thicker wire.. "In circuit" test showed same
primary current and current rise times into primary was all but the same.

 

So, it could be More Reliable and provide the same stats.