Well, what are the pages doing? You're looking at about 150 milliseconds per page returned. Depending on what they're doing, that's either horribly slow or blindingly fast - you've given us no context.
A typical database hit on my 500 MHz celeron-based laptop seems to take 25-100 milliseconds in both Oracle and Postgres. These are informal numbers generated by the acs-developer package that I've noticed while working on OpenACS 4 code.
So if your pages are built using several database queries the number your seeing doesn't seem unreasonable.
On the other hand, if this is a raw HTML page that's simply been put into the www directory of an OpenACS installation, then you've got some very serious problems.
Can you tell us more about the actual pages you're serving?
