[Mgs] Advance curve for MGA 1500

[W. David Houser]

Listers,
Anyone have the information or a website where a friend can find this information?
Seems to me it should be published somewhere….
My friend is looking for….."the advance curve for the 1500, be able to figure out the spring force needed to restrain the mechanism at any given angular shift.”
He has not been able to find springs for same at a reasonable price and is attempting to make his own!
Can anyone help?
Cheers in advance,
Dave Houser