water pressure and flow..what's the ideal combination

[hometech]

Water pressure static is 8bar. Working pressure (if that's the term) is 6bar. Flow rate from cold water is 28-29L/min.
Now this seems good (to me) but reading some suggested figures for ratings at different outlets, my readings seem almost dangerous by comparison.

What should I be aiming for to create what is considered the ideal balance between the two and should I be looking to achieve this using reducing valves?

 

[ShaunCorbs]

Need to bring the pressure down to around 3.5 bar

 

[cjg]

3bar is fine, too high a pressure can cause bust pipes/joints...hope that helps...

 

[hometech]

Need to bring the pressure down to around 3.5 bar

how can I calculate/determine the effect in the reduction in the flow rate when dropping the pressure by half?

 

[cjg]

fit pressure reducing valve