I am using OBD2 connection using fake ELM327 adapter. It is quite expensive for me to buy the genuine one. My dash displays around 20 values per second. RPM, MAP and VSS each update around 4Hz.
If I buy like Vlinker or OBDLink, can I get at least 10Hz refresh rate?
Typically switching adapter will not get you much better data rate. Probably your vehicle is just not sending data any faster.
Some previous discussions about slow OBD2:
slow connection - Connectivity / OBD2 - RealDash Forum
Delay between OBD requests - Connectivity / OBD2 - RealDash Forum