I happen (through FTDNA) to stumble upon a 7th grade cousin: Ton van Vliet. The common ancestor is Gerrit Jansz (Gerrit son of Jan) van Vliet born 31th August 1727 near Utrecht, Netherlands.
In the 37 STR markers we differ in 2: DYS449 (30, mine 29) and CDYa (37, mine 36). So 2 mutations in 220 year or 7 generations (another example of intra familial speeding up of mutations: it should be 420 years).
In the same periode the van Vliet Y chromosome acquired around 5 new SNPs.
So my haplotype is roughly 110 years old?
Hans van Vliet
For both haplotypes of 37 markers, the simple TMRCA=((x mutations x13.5)/2Haplotypes)xYrsPerGen)
What does the FtDNA TIP calculator show?