first connect the tachometer to the rev burner.
Now open the rev burner configuration screen in SimDash.
Look at the firm trackbar, the one near the label "3%".
Move the trackbar until your tachometer displays 3% of its max value, that is 3% of 11.000, which is 330rpm
now consider the 5% trackbar. move it until the tachometer displays 5% of its max value, that is 5% of 11.000 = 550rpm
keep going, do all the trackbars.
the last think to do is to set the "Max RPM value is:" combobox to 11.000