...i am surprised at Ahmed TBH and i do supply him...to use a pump that is just coping...my figure of 380bhp is an average..as said they are rated between 2 figures so some will be less than 380bhp and others more...again i agree new wiring will help the cause.
If yours are dyno figures then you will loose 20 - 40bhp incar.
I recommend above stage 3 044 only and they aint drastically more expensive...if you are lucky to get a better flowing std one then fine..but its not a gamble i would take.