Interesting thought there Charlie...
yes the capacitance does make a difference in it's usefulness
at limiting points wear and tear. (electrical arch energy absorbed
to minimize the spark across the points as they open)
It should be simple to calculate the proper RC (resistance/capacitance)
timing constant F=1/(RC) ( or better stated as RPM/2 =1/(RC)
to best fit a particular ign.coil resistance with
the best condenser for the RPM you drive most often.
I'll have to make up a chart and plot it.
...should be interesting to see the results of plotting energy densities at
various engine speeds.
Paul Tegler wizardz@toad.net http://www.teglerizer.com
OBie - '73 BGT - daily driver
http://www.teglerizer.com/mgstuff/ob_description.htm
Punkin' - '78 Spitfire - corner ripping screamer
http://www.teglerizer.com/triumphstuff/spit78.htm
Lil' Greenee - '73 RWA Midget - lady killer
http://www.teglerizer.com/midgetstuff/index.html
-----Original Message-----
From: Charley & Peggy Robinson <ccrobins@ktc.com>
To: Paul Hunt <paul.hunt1@virgin.net>
Cc: Simon Matthews <simon_atwork@hotmail.com>; mgs@autox.team.net
<mgs@autox.team.net>
Date: Thursday, January 20, 2000 12:19 PM
Subject: Re: Changing condensers/capacitors
Hi Simon,
There's another factor to consider when contemplating changing points
and condenser. Condensers come in various grades and sizes. Say the
one for your B is supposed to be .18 to .24 micro Farads (uF). So
that's (hopefully) .21 uF +/- .03 uF, or +/- 14% in capacity (size).
Cheapy condensers may be made to larger size tolerances (read shoddy
manufacturing). A condenser that's way off in the size tolerance will
result in badly pitted points. I have an old Motors manual that
discusses this phenom. Too large a condenser will result in metal being
transferred to the negative point, too small and the metal mounds up on
the positive point. So if you have points that don't pit badly between
cleaning and regapping cycles, keep that old condenser in there. Better
the devil you know than the devil you don't. JUST BE SURE TO CARRY A
SPARE!
A DISCLAIMER: The mechanic doesn't want to jump to the conclusion that
burnt points are automatically the fault of the condenser.
Contamination is the main cause and we all know that points don't last
long if the coil isn't properly ballasted. One has to make sure that
everything else is OK before suspecting the condenser to be at fault.
End of lecture, ;^)
CR
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