function getPage(thePage,wt,ht,scrollvar){

leftPos= (screen.width-wt)/2
topPos = (screen.height-ht)/2
newWin1 =  window.open(thePage,'aWin','scrollbars='+scrollvar+',resizable=yes,left='+leftPos+',top='+topPos+',width='+wt+',height='+ht);
}

<!--
function renaultf1() {
hauteur=170;
largeur=610;
var winl = (screen.width-largeur) / 2;
var wint = (screen.height-hauteur) / 2;
winprops = 'height='+hauteur+',width='+largeur+',top='+wint+',left='+winl+',scrollbars=no,noresizable';
win = window.open("renault-f1.php", "RENAULTF1", winprops);
}
//-->