I used the Mr Gasket spring kit for the 60's era Fords, it was the only one
I could find that people were still making.
I carefully checked the timing curve before and after the mod.
The initial and total advance is the same, it now just comes in sooner.
There were several better kits available that had different weight springs
that were designed for different applications, but was never bold enough to
try them, as I feared what you mentioned with possible changes in how
initial or early timing could be disturbed by the wrong springs.
It is snowing here again, so I haven't taken it for a test drive yet, but
have high confidence it will improve driving performance based on a friend
here who did the same mod this summer.
Steve
> Steve,
>
>>>>While a change in springs can influence the rate of mechanical advance,
> the total advance is controlled by the weight slot stops.<<<
>
> Yes, that is true, and part of the "potential" problem. I will try and
> illustrate (values are hypothetical):
> Stock springs:
> Initial advance 10 degrees
> Centrifugal advance (at crank) 26 degrees
> Total Advance 36 degrees
>
>
> Softer springs (with distributor NOT moved from previous settings):
> Initial advance becomes 14 degrees (extra 4 degrees come from the weaker
> springs allowing the weight to add centrifugal timing advance - even at
> idle)
> Centrifugal advance (at crank) 26 degrees
> Total Advance 36 degrees (which is where I think your logic is leading
> you)
>
> BUT, if the advance was desired to be reset back to the Initial 10
> degrees,
> the Total would then become 32 degrees. In essence the weaker springs use
> 4
> degrees of the previously available 26 degrees. Thus, the slot only
> "effectively" provides 22 degrees. So, if it was desired to add softer
> springs, but correct the initial advance back to it's original setting the
> (I'll say potential) Total timing could be compromised. Potential - in
> that
> some softer springs might not create the problem, but others, given how
> soft
> the springs are and/or how heavy the weights are, can at times create the
> issues I have presented. At least I have experienced it. Granted I do not
> purchase application specific springs, but grab what I've got and
> "tinker."
> Tinker - which typically involves spending a whole day and often
> ultimately
> deciding I should have left well enough alone! :-(
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