164 leaky cat. and NOLOGY vs. Magnecors

[mfd164@domain.elided]

OK. To recap, the MSDS conical filter I put on Gabrielle was causing her to
choke up beyond about 5K rpm- it just wouldn't wind out any more, unless
very little throttle was used, and a lot of patience from me. I found a
small hole in the cat., just to the right of the O2 sensor, and on the
bottom half of the assmebly, but still on the side of it. It's about one
inch long, and about a pencil's width across. Would this be big enough and
in the right place (ie far enough ahead of the sensor, or at least in a
place that would let more gasses out or something) for it to cause the
sensor to get wacky? That would actually be relieving, given cost of new
parts vs. going to midas to have them weld a piece to my cat. Any thoughts
are appreciated. 
NEXT, anyone have experience with both Nology and Magnecor wires?
Preferably, one person who has used both on the same car (164 preferred but
not required). Pluses, minuses, general impressions, scientific data, etc.
I've read the Digest FAQ and looked at both companies' sites, and want
comparisons for the two if they're out there. Thanks a bunch! 
Mark Domby
91 164S  Gabrielle

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