As a Roblox Developer, there is currently no way to replicate the behavior of RodConstraints when LimitsEnabled is set to true, without the .Length constraining part.
If I wanted to limit the maximum angle that either end of the rod may have against the respective attachment, I have to also constrain the distance between the two attachments, because that’s the primary purpose of the RodConstraint.
I have needed this constraining behavior (minus the length constraining), for many things, primarily a rope hanging from a helicopter, that the size of I want to be controlled by a RopeConstraint, but also another constraint that does RodConstraint’s of limiting the angles, without limiting the length. Many applications using rope that want to limit the cone of freedom of one of the attachments, mainly so the RopeConstraint doesn’t freak out, suffer from RodConstraint also constraining the length.