Probably not.
The reason people up their voltage is because their system is unstable at overclocked speeds without more voltage.
To find out if your system is stable, do some tests, for example:
download the latest bug fixed version of Prime95:
http://www.mersenne.org/freesoft.htm
Double click on PRIME95.EXE to start the program.
Just Stress Testing (if prompted) > OK >
Options > Torture Test > Blend (if prompted) > OK
The program should not give any errors.
It may be necessary to run the program 12-24 hours to make sure an overclocked system is stable (no program errors displayed).
If you wish to overclock your system further, 2100+ retail heatsink is not good for overclocking but if you get an all copper heatsink and if you have a name brand power supply, 2100+ is an excellent overclocker, (provided it's a 2100+ Thoroughbred B).