The forces exerted on the blades are a function of mass times
acceleration. It sounds like you are already affecting the mass part
of the equation ("thicker, wider and longer"). The acceleration is a
function of the rotational velocity. Its an unknown unless you have
the specs of the Delta and Ridgid to directly compare. Your proposed
substitution may be drastically exceeding the design specs of the Delta
cutter head or the Ridgid blades or both, the result being catastrophic
destruction at an inopportune moment.
In other words, its a dangerous substitution.
Bob