Hi Paul, Larry . . .

I am not sure that I am following this discussion.

In Bill Fisher's book he talks about 'chopping' the weights in the distributor by clamping them together and grinding off an equal amount of metal. He recommends doing this in relationship to the amount of increase in compression ratio over stock. This seems to make sense because the effect is to 'reduce' the rate of the mechanical advance as RPM climbs. Which means less spark lead in the lower RPM range. In my mind lighter weights or stronger springs would have the same effect on advance rate.

When you guys are talking about recurve (because of a longer duration cam) do you the mean the rate at which advance takes place - or the total number of degrees the mechanical advance mechanism can introduce? Or Both?

Since a longer duration cam will move the power band up the RPM scale - wouldn't we want to reduce that rate of the mechanical advance?

regards,
Keith

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