Preschooler time measurement

Son: are we nearly there?
Me: 36 minutes.
[Four minutes later]
Son: are we nearly there?
Me: 32 minutes.
Son: that's longer than *muffled word*
Me: no, it was 36 before - that's four minutes shorter.
Son: oh mama, I didn't say longer than before, I said that's longer than a Porsche.
Me: oh...yes...yes it is...