Patience, patience,

While what you've described is possible, you need to get to first base before you can get a home run.

If you made the changes I suggested, then at 4500 RPM you should now be getting a constant capture result of around 6666.

Other RPM's should give the following results.
RPM - Capture
--------------------
500   - 60,000
1000 - 30,000
2000 - 15,000
3000 - 10,000
4500 - 6,666
7000 - 4,285

The formula in your program is still the same as what I gave you for the Pulsin readings. This will no longer work for the capture results and needs to be changed.

But first, can you verify that you are getting the correct capture result?

Best reagrds,
   Darrel