Re: IML: dual point distributor questions

[sosmi@xxxxxxxxxxx]

The dual point distributor, was designed for HI-PO applications. The Chrysler dual point, had 2 sets of points to handle high RPM, and reduce the current through one set of points, they also ran higher spring pressure to prevent point bounce at high RPM. Mallory came up with a distributor called Double Life, it also had 2 sets of points, but they fired alternately, and also" Doubling" point life. After many years, of racing and performance tuning, I've found, the best thing is remove the distributor, and adjust each point set to.016-.019 I prefer going on the high side, because the point rubbing block wears, and you loose the spec. quickly. Checking dwell, is a waste of time, because the point gap will allways be between .016-.019 The other thing you could do, is convert to electronic, with a pertronix kit.Ya'll have a nice day, Dave.

 

-------------- Original message --------------
From: therichardsonfamily@xxxxxxxxxxx

Hello everyone:

 

I have a '67 440cid Imperial motor that has a Mallory Dual Point (#ZC365HP) distributor on it.

 

Question #1 - exactly how does a dual point work?  Does one set of points deliver spark to 4 cylinders, and the other set to the other 4?  What is the high performance advantage to a dual point?

 

#2 - I don't see a way to adjust the dwell when the car is running - is that correct?  I check the dwell, shut it off, pop the cap, and guess at the adjustment?

 

#3 - I thought the FSM said to insulate one set of points while checking the dwell on the other.  If one set runs 4 cylinders, that won't work out so well.  How do I check & adjust the dwell on this Mallory distributor?  What am I missing here?

 

#4 - Do I set timing first, then the dwell?  What are the correct steps?

 

This one is right up Uncle Rodger or Dave's alley (two guys that seem to have forgotten more than most of us will ever know about these things)!!!

 

Thanks in advance,

 

Dan Richardson

300L Family Heirloom