Reducing max pressure relief with a shim kit does not reduce the pump flow. Excessive pump flow produces excessive heat - just like putting a high volume / high pressure oil pump unnecessarily into an engine and dealing with superheated foaming oil. Higher max pressure relief is "good" when in proper spec, while high flow is "bad" when too high, requiring a mandatory large cooler installation just to keep the PS system operating temps reasonable.
Philly, call my guy Jim and enjoy a good conversation:
http://www.hydratechbraking.com/contact.html
