pipe delay issue

[simoneweb]

Hello folks,
I did created 2 pipes 1 for download and 1 for upload.
I can control the bandwidth separately without any issue, i.g down 10mbps and up 5mbps. the issue is when I add latency to just one of the pipes let's say I add 50ms delay to the "download pipe"... also the "upload pipe" is affected.
so the result is 50ms added delay on both pipes.
down pipe [original latency + 50ms delay = 100]
up pipe [original latency + 50ms delay = 100]

this is what I am trying to do:
down pipe [original latency + 50ms delay = 100]
up pipe [original latency + no delay = 50]