radiator caps, cooling system pressure

I was thinking of putting a higher pressure cap on one of my cars to
increase the factor of safety against boiling. Looking thru the web
for info on the likelihood of changing from 7 psi to 13 psi causing
leaks I found little on that issue but did find a couple references to
the pressures created by the water pump. One site boasts of a 19 PSI,
$25 cap to get you thru your "hard driving".
http://www.mishimoto.com/mishimoto-h...ap-13-bar.html
Thought I'd see if anyone else has heard of this. The claim was that
the water pump could create over 30 PSI of pressure. Since that is
double the normal operating pressure of most modern cars I find it
hard to believe. If the system was at full 15 psi of pressure while
the car is idling and then your floored it and ran it up to near
redline and created another 30psi of additional pump pressure, or
even 10 psi of additional pressure downstream at the radiator cap, you
would immediately cause the system to have to vent to the overflow to
relieve this higher pressure. I've never seen a car vent due to me
revving the engine up while I'm working on it. Thoughts?????