<VV> Dual Points-advantages?

[Sethracer at aol.com]

In a message dated 2/12/2006 12:10:46 PM Pacific Standard Time,  
daretocorvair at yahoo.com writes:

As far  as I can tell, the advatage of a dual points
system is that each set does  the job half as much as
they do with a single point system....while one  is
firing, the other is closed...so they last twice as
long by doing  half the work.

True?

what are some other advantages.

Ryan  V.



There were two very different "dual-point" Mallory distributors made for  the 
Corvair. The old-style one used a special 3-lode cam. Each set of points  
controlled the firing point for three cylinders. Actually, since they  
alternated, one set of  points fired one side of the motor, the other set  the other 
side. The advantage of this set up was the shape of the cam used to  open the 
points. Since it had plenty of time to fire three times, it was a very  easy, 
gentle, slope up and down, to open and close the points, quite  different than a 
stock set-up - That made it better for high-RPM use, since you  were quite 
unlikely to "Float" the points. (A similar set-up was used on the  Mallory for 
the eight cylinder motors - a four lobe cam) The down side was since  each set 
of points fired a side of the motor, when checking the timing you had  to check 
cylinder Number , then cylinder Number 2. ANd if they were different,  adjust 
the dwell on one set or the other. It made a distributor machine almost  an 
imperative! The later ones used the classic one set to make, the other to  
break, style. Mallory finally made a conversion kit for thes distrbutors to add  a 
Unilite conversion. If you must use a Mallory, That is the only set-up I  
suggest. The later ones also used a standard design distributor cap so you can  
use normal wires. I have made wire sets for the two-piece Mallory cap. It is  
okay, but it is solving a problem we don't normally have on the Corvair.
 
- Seth Emerson