I worked it out.. For anyone else that is curious..
[code=php]
$date1 = '20050616000000 ';
$year = substr("$date1", 0, 4);
$month = substr("$date1", 4, 2);
$day = substr("$date1", 6, 2);
$hour = substr("$date1", 8, 2);
$min = substr("$date1", 10, 2);
$sec = substr("$date1", 12, 2);
$week_end2 = date('YmdHis',mktime($hour,$min,$sec,$month,$day +7,$year));
[/code]