求个延时弹出窗口的代码

<script language="javascript" type="text/javascript">

function opentit()
{
var newwin = window.open("http://www.163.com");
}

function delayopen()
{
window.setInterval("changeit()", 1000);
window.setTimeout("opentit()",4000);
} function changeit()
{
var con = document.getElementById("time");
var ctime = new Date();
con.innerText = ctime.getSeconds();
}</script>
</HEAD><BODY>
<div id="time"></div>Second<br/>
<INPUT TYPE="button" value="Normal open" onclick="opentit();"><br/>
<INPUT TYPE="button" value="Delay open" onclick="delayopen();"><br/>
</BODY>
</HTML>