I'm trying to use the CRC module on my K60 MCU to generate CRC 8 code. I checked the methods in PEx and I found it not possible. It seems that the poly should be at least 16bit.
8-bit CRC actually is possible with a 16 or 32-bit CRC module.
You can convert the 8-bit polynomial into 16-bit by shifting 8 bits to the left, and then to get a 8-bit result do the same to the resulting 16-bit CRC. Similarly, with 32-bit you would need to shift 24 bits to the left.