Multiple Classes to Speed up Iterations

I have written a piece of product selection software which requires a massive amounts of iterations, unfortunately these are unavoidable, (its the nature of the beast,) and each iteration uses our suppliers .dll.
So this takes time.

I was wondering if I made the code into its own class and make multiple instances of this class, each with different parameters which need refining. Would they all run in tandem and speed up the process instead of doing each one after the other.

Nope. Single threaded still.

You may want to consider creating an ActiveX EXE which can provide/imitate multithreading. Search forum for examples/threads using those key words: ActiveX exe multithread