Thanks for the reply guys. I'm using hfsc + altq and would really like a
finer grain clock for better bandwidth management on low bandwidth queues.
Though I didn't get a "how to answer" for this question I managed to get the
clock to 1000hz by modifying the source file /usr/src/sys/conf/param.c,
#define HZ 1000 and recompiling the kernel. Everything running fine so far
and pf + altq seem to be doing a great job at shaping my network traffic.

If I do have any problems with my new kernel I'll be sure to switch to a
stock version and test before requesting help.
Thanks to the OpenBSD team for their hard work and dedication to this great
product.
-- 
This is too troublesome