how to convert the x axis of a time series autocorrelation from time lags to real time?

Hi all, I have a time series with 32000 samples. I have plotted the autocorrelation of the time series by autocorr(x,n) syntax. where n is its lag. it plots the autocorrelation which its x axis is based on the time step, but I want to convert the x axis to real time which totally is 0.16 sec. any help would be appreciated.