Baud rate should have nothing to do with it as such.
I am always not getting the full 2000 * 17 bytes
How many are you getting?
What data are you sending and what are you receiving?
How fast is the Serial.print running? If it's < about 15x (the length of "I received: nn") the 4800 baud you may be overflowing the receive buffer.
You need to post both halves of the code.
Rob