The VAX builds usually take about 5h wall time. That host is a HP ProLiant DL360e Gen8, 2x E5-2450L, 64 GB RAM, 3 TB HDD. Would be nice to have a really modern system, but that came from my employer and was just around for free. (5h here also implies that I usually run 14 jobs in parallel overall.)
lol :) So yes, your box is (at least) 1.7 to 2 times faster.
Wait - five hours wall time, while running -j 14? Or are you saying you're running 14 simultanous ./build.sh builds?
On the same 5900X with -j 24, even when it's busy with lots of other things, it's 2028.91 real, or 34 minutes (for -x tools distribution release iso-image install-image live-image). it's 1288.80 real on a 5950X with -j 32, which is nice :)
John