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Old 11-24-2010, 10:10 AM   #20
Michael Mayben
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Join Date: Jan 2007
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Age: 71
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Default Re: marquette engine analyzer

Quote:
Originally Posted by rwerth7 View Post
from what u can see will it work on a 66 corvette with an after market pertronix electronic ignition in place of the points (has distributor and coil)?

Thanks.
If that analyzer actually operates, it would be absolutely perfect for your 'vette motor or any other package from that era!

A pertronix conversion for any distributor is a "hall effect" technology. The actual electronic component is the same for any distributor application, no matter what "brand".

And yes, a pertronix will trigger any of these analyzers. But...they won't read a capacitive discharge system triggered by a pertronix or points. That would be something like the mallory/msd/crane/accel "six" series boxes.

Even an engine equipped with the delco hei electronic ignition which came later on the 'vettes will read of course as we previously mentioned. An hei system is an inductive system and bears no relationship to a capacitive discharge system.

With a pertronix conversion in the distributor, your "firing line" pattern on the scope (primary ignition pattern) will still display a dwell reading just like breaker points. That is because the actual "dwell" is a function of the air gap between the magnet wheel and the pickup on the pertronix. Assuming you are using the traditional delco distributor that was oem on the 'vette (and all GM products of that era), that distance had to have been "adjusted" when the pertronix conversion was installed. And the actual dwell you see displayed on the scope will be the same as what it was with breaker points only it will display as a very accurate "trigger signal" instead of the somewhat wavering signal provide by the points/condenser which is an electro-mechanical device and not nearly as accurate.

A pertronix dwell will also display correctly on any analog "stand-alone" dwell meter.

I'm attaching a basic scope pattern interpretation of the primary signal for you, this is from a college-level textbook that I used when I was teaching this stuff years ago.
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