Upload speeds extremely higher than download

[daishi55]

When I start a torrent, within 10-15 minutes I have reached my peak download speed, which is around 40kilobytes/sec. I was at my friend's house today, who has the exact same ISP and internet plan as I do (1.5megabyte/sec DL), and within 30 seconds after starting the torrent, he was getting the full 1.5MB/s download speed. Additionally, if I don't set an up limit, upload speed can easily reach up to 700kbit/sec, while the download remains below 50. Here are my settings (I used the conservative settings chart on this forum):

Max upload (kB/s): 140

Max download: unlimited

Global max connections: 250

Max connected peers per torrent: 60

Upload slots per torrent: 7

Use additional upload slots if up speed < 90%: unchecked

Outgoing encryption enabled, incoming legacy connections allowed

Max active torrents: 8

Max active downloads: 7

UPnP/NAT-PMP enabled, added Win firewall exception