Distributor springs

Pink is around 1.1 to 1.7 lbs/in. and the shortest at .56"
Orange from mallory worked out to 13.3 lbs/in but the one in MP kit was 8 lb/in by my calculation and 6.5 lb/in according to them. It was also the longest of the primary springs a 0.635"
The long looped silver springs are around 28 - 30 lb/in and at .815" slightly longer than the long looped purple, which has slightly lower spring rate.

The springs in the Crane Kit for GM points distributers are around .6" and vary in spring rate from around 11 lbs/in to 24 lbs/in
Gardner spring available from hardware stores is also around 24 lbs/in rate but its .75" long. Can also buy it from McMaster as p/n 9044k171

Check the inside diameter needed for the Mallory YT - YH advance to fit on the spring perches.
I'll look through my experiments with the mallory based distributor to see what I did that might be helpful. I know my current setup is a slower advance, but I think less degrees than your planning. It might be using the Crane Blue spring with the silver secondary spring.

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