Hop alphas etc on etract brewing

[juuunx2]

Can anyone advise me please. I have made several great extract brews folowing recipes. I now want to try a brew myself, picking my own hops etc.
If i was to do a single hop brew like say amorillo for example but use a different hop like say the new Wai ti New Zealand hop should I use similar ammounts of hop. Amorillo has an alpha content of 11.2% wheras Wai ti just has 4.5%. Does this mean A) that I should add more of the Waiti to achieve same effect or B) I should use simmilar quantities and do the boil longer to extract more flavours???
I should have probably posted this in the hop section sorry.

If anyone can help It would be much appreciated
regards all
Mart

FV1: Amorillo
FV2: Country gold
Conditioning: around 300 bottles various
drinking:Exe valley spring and Summer glow

[brewnaboinne]

you have to use more of the waiti hops in inverse proportion to the Alpha content i.e. about 2 1/2 times as much from the bittering point of view.The hop utilisation won't increase much more beyond 90 mins.boiling.

[juuunx2]

many thanks I will try that

Mart