Be careful! Is that max advance spec supposed to be
degrees at the crankshaft or at the distributor
itself?
These specs are often quoted as degrees at the
distributor, because that's what you measure on a
distributor testing machine.
There is a 2:1 difference between the two measurement
systems, because the distributor is turning only half
as fast as the crankshaft. So 27 degrees of
distributor advance would show up as 54 degrees of
crankshaft advance.
But after checking my Bentley manual, it seems that
most Spit distributors have about 16 to 20 degrees of
distributor advance at 2500 RPM, which translates to
32 to 40 degrees of crank advance at 5000 RPM.
But I do know that the timing mark will run off the
end of the scale at high RPMs- there are simply not
enough degrees on the scale to show the correct full
advance.
Anyway I do not think it is easy to find the correct
springs. The problem is that there were so many
variations for the different models over the years. I
think a real distributor shop would have a big
collection of generic springs, and they would find the
correct ones by trial and error on a testing machine.
Doug Braun
'72 Spit
> I checked the timing on my spit this weekend with my
> new Inductive Timing
> Light (anniversary present, got a good one.) and
> discovered that my
> centrifugal advance is advancing WAY to much (Max at
> 5800 is suppose to be
> about 27 degrees. My timing mark disappeared!).
> So, where can I get some
> new advance springs and is this something that is
> easy to change?
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