Resampling necessary?
Resampling won't change the signal duration. It will change the sample rate and the number of samples. And, if you're lowering the sample rate, it will change the frequency components of the signal (if done right, with a proper filter, it will reduce the maximum possible frequency to half the new sample rate).

In order to make your signal "faster" or "slower" you need to use a different technique, time compression/expansion or simply time stretching. The basic idea there is to split the signal into blocks, estimate the frequency components in every block and then replace each block with a block of shorter or longer duration containing synthesized sinewaves of the same frequencies and phase shifts. It appears that currently there's no high quality method for time stretching signals by more than 30%. All cheap methods distort audio signals noticeably to the ear.

What is the problem that you are trying to solve? What's the nature of the sampled signal? Can you expand your question?