RE: Distributor Tester Findings

[Doug Rasmussen <76075.2276@domain.elided>]

  >>From: Tom and Amanda Lang <rustnrot@domain.elided>
  >>Subject: Distributor Tester Findings
  >>Somehow I lucked into a "Allen" (manufacturer) distributor tester circa
  >>1950 in excellent condition and working order at an auto swap meet in
  >>Albuquerque, NM a year or so ago for $30, yep, thirty dollars.  Even has a
  >>separate box that has a gauge on it that measures exhaust gases.  Anyway,
  >>I've only played with it one time.  I had several distributors laying
  >>around, mostly I-H.  What I found amazed me.  All the distributor
  >>*mechanical* advances were within 1 degree of spec.  The vacuum advances
  >>were all within a couple of degrees or so if I remember correctly.  Anyway,
  >>the moral of the story, based on my limited sample, is that distributors
  >>stay within spec remarkably.  Soooo, don't assume just because "it's 25
  >>years old" that it *needs* to have the timing curve set.

Tom,
  When I use the term *recurve*, what I mean is to *change* the timing advance characteristics to something other than the way the distributor came from the factory.  From the factory, the distributors would be setup with a timing advance curve that was the best compromise for the intended purpose of the vehicle. For example, a Scout wouldn't use the same timing characteristics as the same engine setup for a marine application.
  And, if you've modified the engine by switching cams, etc,  you'd probably want to change the advance curve to reflect the modified engine's needs.
  When I check my shop manual under distributor test data, I notice the advance curves for the different points-type distributors that fit the V266 to V392 can vary quite a bit.  So, if you were switching to a reliable points distributor from the gold box electronic type, you might want to *recurve* to match the specs of the original non-points type.  In other words, all IH distributors are not created equal!!!
  The whole concept of *recurving* is a good excuse to buy a Mallory.  With the Mallory,  you just  *recurve*  with their kits.  And, as the Mallory comes out of the box, you start with a more performance oriented advance curve. 

  Anyway, that's about what I know about *recurving*.  Sounds like a deal for a distributor machine at $30.

Doug