[FC] Rampy issues

[Rad Davis]

Three reasons to use electronic ignition on a Corvair:

1. hotter (higher voltage, more current) spark.  Yes, significantly 
hotter - the points don't have anything like as rapid an opening time, 
and dwell is...variable on the Corvair distributor with points at best.  
It will start noticeably better when hot and on really cold days.  This 
saves wear on the starter and aggravation on the driver and reduces 
likelihood of flooding.

2. Crappy stock distributor.  There are good point distributor designs.  
Bosch made some nice ones.  The V8 Chevy distributor with the dwell 
adjustment window in the cap isn't bad.  The last Chevy breaker points 
six-cylinder distributor is junk.  Even if the shaft bushings have the 
perfect .00125 clearance and the distributor cam has minimal clearance 
to the shaft, you still have to deal with the flaky point plate design, 
which features a rapidly wearing steel-on-steel pivot and a 
non-concentric motion that guarantees that dwell is variable as vacuum 
advance changes.  In the real world, the effort of opening mechanical 
points against the spring causes the advance cam and point plate to 
bounce around while the engine runs..  Maintaining all the clearances at 
unpublished 'factory spec' minimizes, but does not eliminate these 
problems.  Optically or magnetically switched electronic.ignition does - 
it removes the radial load on the distributor shaft and point plate 
entirely, and also has no mechanical hysteresis in its operation.  The 
distributor settles into a steady state of operation and is much more 
consistent.

3. Better fuel economy.  The combination of 1. and 2. above mean that 
you can run more spark advance and a wider spark plug gap, both of which 
improve power and efficiency, although you will probably have to invest 
in a set of Seth Emerson's wires to manage the extra 10,000 or so volts 
you'll be making (more if you also run an aftermarket 'hotter' coil, as 
I do).

All Corvairs come equipped with a handy storage compartment in front of 
the passenger's seat that does a fine job of holding a sandwich ziplock 
bag containing the stock point plate you removed when you switched to 
electronic.  That and a matchbook cover will get you home in the event 
that the electronics give out.  In practice, I've never had one fail in 
several hundred thousand miles of driving of several Corvairs.  I 
suspect that failures were much more common in earlier generations of 
aftermarket electronic ignitions.

Kettering ignition is an elegant and simple design.  But turning a 
mechanical switch on and off 25 or more times a second to run your car 
because you're unwilling to admit that solid state 1960s technology 
might be superior to electromechanical 1915 technology is neither.

-Rad Davis


On 6/23/2011 5:05 PM, Chris & Bill Strickland wrote:
>> Then install a pertronix (or similar) and never look back.  (Carrying stock points plate setup for spare).
>>
> That almost sounds oxymoronic!  Why not just skip the failed electronics
> step, install the stock points plate setup, and carry a spare condenser
> (or two), a points file, some distributor cam lube, a small screwdriver,
> and a timing or test light ...
>
> And a spare fan belt and wrench, and a spare tire, jack, and lug wrench ...
>
> Here is an interesting and perhaps educational version of one person's
> take on Points Ignition Theory --
>       http://www.mgb-stuff.org.uk/ignitiontext.htm#theory.
>
> As an aside, I have found Standard's "Blue Streak" line of condensers to
> come in a box labeled "Made in USA", meaning the condenser, I presume.
>
> Bill Strickland
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