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Re: Electrical Tune Up & Electronic Ignition

To: alemen@pop.ftconnect.com
Subject: Re: Electrical Tune Up & Electronic Ignition
From: "Donald H. Locker" <dhl@chelseamsl.com>
Date: Sat, 17 Jun 2000 22:35:33 -0400
Hi, folks.

FWIW, there are several advantages to a properly installed and
well-designed electronic ignition.  Everything else that I can think
of is smoke, mirrors and marketing hype.

1.  elimination of point bounce, particularly at high speeds.  This
    allows the coil to be [more] fully charged so that it can deliver
    spark as needed.  When the points close, the contacts can actually
    bounce open several times, each opening reducing the actual time
    that the points are closed.  This is usually necessary because
    people have their foot into it and combustion chamber pressures
    are higher, especially if the intake and exhaust systems are
    properly tuned.

2.  intelligent electronic ignitions can increase the dwell angle at
    higher speeds, again for a healthier spark.

3.  reduction of spark scatter -- any deviation in timing due to cam
    and cam follower wear and advance sensitivity in the cylinders due
    to hotspotting, compression ratio differences, induction
    characteristics, whatever, requires that the ignition timing be
    retarded so that no cylinder ever consistently sees a too-early
    spark.  Well-designed electronic ignition systems installed
    properly reduce the scatter so that the initial timing can be set
    more advanced, and total timing will be operating closer to the
    optimal.

4.  the reliability of modern electronic ignition systems is more
    reliable than vintage electronic ignitions, which were somewhat
    more reliable than points systems.

Donald.

> From: "alemen@pop.ftconnect.com" <alemen@pop.ftconnect.com>
> Date: Fri, 16 Jun 2000 12:47:23 -0400
> 
> 
> Bob, I second your query. I similary would like to know as my 76 has
> electronic ignition, but it's old and is it worth replacing - I plan
> on getting some more bhp in the future without major mods (twin SU
> or similar, street cam and freer flowing exhaust). Does a Crane or
> Pertronix really do anything for us and also would a new coil also
> help with a higher voltage spark. I do have all the other parts
> replaced already (plugs, leads, rotor & cap) and as it's a 76 I do
> have the 9:1 compression ratio.
> 
> Alan
> 
> Original Message:
> -----------------
> From: Bollinger, Bob D. (BODB) BODB@chevron.com
> Date: Fri, 16 Jun 2000 08:57:49 -0700
> Subject: Electrical Tune Up & Electronic Ignition
> 
> 
> 
> I have a '79 Spit and am slowly doing little things to try to boost
> performance.  I've seen a recent post by a lister who did kind of an
> electrical tune up.  My question is what should I replace/upgrade since I
> know nothing has been done in a long time on the car:  plugs, ignition
> wires, coil, and "stuff" in the distributor (this is where I'm really
> fuzzy)??
> 
> How about electronic ignition?  In the recent issue of Spitfire Magazine
> there was a recommendation to upgrade to electronic ignition.  When I look
> at the car's specs in the Haynes manual it looks to me like it says I
> already have "pointless electronic ignition" or something like that (I don't
> have the manual in front of me).  Would getting one of those Crane
> electronic ignition kits be an upgrade or something different from what's in
> the car now.
> 
> Thanks for any insights for this electrical system challenged Spitster.
> 
> Bob Bollinger
> '79 Spitfire

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