It doesn't exist, but I believe someone was working on it. You could try it with trial and error. The cts3 modifier works like this: "Ceil(Sqr(Tol*CTS3Modifier));" You can achieve the same with editing only one of them. L*a*b are compared against each other with that tolerance.
Where:
L = L1 - L2
A = A1 - A2
Bb = B1 - B2
Simba Code:
(L*L + A*A + bB*Bb) <= i.Tol;
edit: Tell you more? uhm, any change if you start reading at line 256 you will understand it? https://github.com/MerlijnWajer/Simb...ore/finder.pas