If the time is incorrect it sounds like either you're not using NTP or the NTP source is misconfigured.
If not using any NTP sync then the servers will drift over time as the onboard clocks are not that great.
Try WMI to get the time. Get-Date should be displaying the local time on that server, but I've had Get-Date automatically convert UTC\GMT to local time on me before. Your not really explaining how the remote servers are configured. Are you seeing the time off by 20 minutes? Are you seeing that the date is in EST on the server but is converted to PST?