Don't do this to your engine.
If:
a) You already have a problem with your engine (burns oil, lacks compression, gasket leaks)
then no bullshit additive is going to help your case, other than taking whatever is broken apart and fixing it
b) You do not have a problem with your engine but you just want to flush it well
buy some synthetic oil, do the oil change and keep the old filter, drive for a week and do the oil change again and now replace the filter. This is a LOT better than any engine flush additive you can think of.
I would however go with
c) If it is not broken, don't fix it.