RE: Mallory distributors

[Doug Rasmussen <76075.2276@domain.elided>]

>From: Jean Tkachyk <tkachyk@domain.elided>
Steve wrote:>
>I can't seem to tune the engine properly with some of the previous 
>owners modifications. I have a '79 scout (345, 2bbl Holley not orig., 
>4-speed, non-electronic distributor not orig). The distributor that was 
>in the Scout when I bought it last year had bad bushings and I replaced 
>it with a Mallory dual point, it already had the mechanical dist. The 
>preivious owner also removed all of the smog stuff from the orig Carter 
>carb. and installed a 10" air cleaner. A manual choke was also 
>installed. With all of these mods. I'm only guessing at what the 
>timing/idle/dwell should be and what the points should be gapped at, and 
>what air/fuel mixture should be. Currently running at 800rpm, timed @ 0 
>degrees TDC, and points are gapped at .022, total dwell 33 degrees ea.@ 
>26 degrees. I got the dwell and gap info from supershops when I bought 
>the merch. After start-up the engine runs OK, but surges occasionally 
>and sometimes sputters on acceleration. Also it will need considerable 
>warm-up time to get to running smoothly @ 800 rpm. Strange since I live 
>in Tucson, AZ. Sorry about the long post. Thanks in advance for your 
>help, Steve
<

Steve,
  Here's a guess at your problem.  I suspect your timing should be advanced more.  The mallory distibutor mechanical advance doesn't kick in until 1000 rpm so I'm thinking that with the Mallory the initial timing should be set to something like 6-10 degrees BTDC.  Also, since your engine has been modified I wonder whether it's using manifold or ported vacuum advance.  Depending on which, you might or might not have any initial advance at idle.
  Regarding Mallory distributors, I found out some more stuff from Mallory.  They told me the IH gears that fit directly onto their distributors are ones with a bore of .491".  Some good news, SuperShops sells Mallory 276-1701 (dual point, vacuum) for $129!!!!  The bad news is SuperShops just declared bankruptcy.
Doug