[T3] Blue Coil

[Jim Adney]

On 29 Jan 2011 at 13:23, Keith Park wrote:

> Yep, same company that makes the auto trannies too.

Yes, B-W makes lots of gearbox stuff, and turbos, too, I believe, but 
no one I've talked to thinks they have any electrical production of 
their own. Anyone can arrange to market someone elses product if they 
sell enough of them. The only problem is that this becomes an unknown 
quantity, unless someone in the know can tell us who actually makes 
it and then we might be able to guess what the quality might be.

Nevertheless, I think it's likely that his coil is okay. Coils seldom 
fail.

> The coil and condenser (capacitor) are a matched pair, as is the coil and
> the ballast resistor if it has one.  Ill be the stock T3 condensor is not
> the match for the Borg warner coil and hence the problem.  

We've been over this before. There's no "matching" or tuning. You can 
measure VW, Ferrari, and Chevy condensors and they all have the same 
capacitance, which I believe is about 0.2 uF. What it comes down to 
is the fact that over the years, everyone settled on one central 
idea.

The proof of this is the fact that Bosch will sell you a Blue coil, 
which has quite different inductance, without providing a different 
condensor to use with it. If you test a 009 condensor, you'll find 
the same 0.2 uF (+/- 10%.)

For some makers, Chevy comes to mind, they made different condensors 
available, but those were just to provide faster spark rise times for 
use at higher rpms (and they work WORSE at normal rpm.) This is 
almost the exact same problem that we get into with the Blue coil 
when used at low rpm: The inductance is lower, the rise time is 
faster, and the low rpm current thru the points gets excessive.

-- 
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Jim Adney, jadney at vwtype3.org
Madison, Wisconsin, USA
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